Reaction to the disaster from Daisuke Tsuchiya, First Secretary at the Japanese Embassy in London: "It's an absolute shock to everyone in Japan. And the effects, including the devastating tsunami, are really unspeakable... We've been able to, I believe as a government, move quite swiftly in terms of sending out our self-defence forces, rescue and operations. But of course, the power of nature is indeed very strong. At this stage, it really is difficult to assess the actual damage."
Dr Susan Hough, a seismologist at the US Geological Survey in California, tells the BBC: "Sometimes you seem to get a cluster, and this has happened a few times that you can think back to. In 1999, there were a couple of big earthquakes, and just last year there were a lot of the same questions because we had an 8.8 off of Chile very close to the Haiti earthquake."
Charles McCreery, the director of the Pacific Tsunami Warning Centre in Hawaii, writes: "It's a huge area that's affected, and when you move that much seawater, you start the tsunami wave and it essentially propagates across the entire Pacific in a frictionless fashion, so it doesn't lose much energy."
An account of the moment the earthquake hit from Niel Bowerman, of Oxford, who was on a train heading into Tokyo: "The train emergency braked and shook around like crazy. I thought it was going to be thrown off the tracks. The train was on a viaduct and I was also worried that the viaduct was going to collapse. The smell of burning rubber was strong. After 1.5 hours of sitting in the train with many strong aftershocks, we were evacuated. We walked along the track for 20 minutes to the next station. There was visible damage to the viaduct - bolts ripped off and supports out of place."
More from the Tokyo Electric Power Company: It says the ability to control pressure in some of the reactors at Fukushima-Daini has been lost. Pressure is stable inside the reactors, but rising in the containment vessels, a company spokesman says.
Italian teacher Giuliano Bettolini tells the BBC it took him 13 hours by car to get from Higashinatsuyama in Saitama prefecture to his home in Tokyo - a journey that normal takes him two hours. He says: "It felt like I was in a Hollywood movie... lots of people were walking home and around the city."
James from Easter Island, writes: "I'm the British Honorary Consul here on Easter Island. Everyone now evacuated from the low parts of the island and all gathering in the airport. Tsunami due to have arrived 1 minute ago. No changes here yet, just an eery silence."
The Tokyo Electric Power Company has said the cooling systems of three reactors at second nuclear power plant, Fukushima-Daini, are malfunctioning, according to the Kyodo news agency. The plant is 11km (7 miles) to the south of Fukushima-Daiichi, where the cooling system one of its reactors is not working and pressure is rising.
Japanese nuclear safety officials have said the problems at the Fukushima-Daiichi nuclear power plant represent "no immediate health hazard" to people living nearby. Some 45,000 people living within a 10km (6-mile) radius of the plant were told to evacuate as radiation levels rose to 1,000 times above normal in one reactor.
Saori, from Tokyo, writes: "It's amazing how the internet has provided us with so much information. Twitter and facebook is the fastest way to keep in touch with family and friends right now."
Other islands in the South Pacific have been reporting bigger-than-normal waves as the tsunami reaches them, but no significant damage. Police in Tonga said water had surged into a number of houses on the low-lying Ha'apai islands early on Saturday morning, according to the Associated Press. Tidal surges up to 66cm (26in) high were also reported in American Samoa, Nauru, Saipan and at the far northern tip of New Zealand.
Chile's Interior Minister, Rodrigo Hinzpeter, has ordered the evacuation of "all people living in defined flood zones" ahead of the expected arrival of tsunami waves of up to 3m (10ft) along the country's 4,000km (2,500-mile) coastline. On Easter Island, in the South Pacific, the authorities have evacuated 1,500 residents to the airport, which is 45m (150ft) above sea level. The tsunami is expected to reach Easter Island shortly before 1800 local time on Friday (2300 GMT). Residents of the Robinson Crusoe islands, which are closer to mainland Chile, have also been told they may have to move to higher ground.
The Associated Press is also now citing Japanese nuclear safety agency officials as saying that radiation levels inside one of the reators at the Fukushima-Daiichi nuclear power plant have surged to 1,000 times their normal levels after the cooling system failed. Pressure inside the reactor has risen to 1.5 times the level considered normal.
As dawn breaks across Japan, the scale of the disaster is becoming clearer. Fires are raging across Kesennuma in the north-east, according to the Jiji Press news agency, and one-third of the city has been submerged by the tsunami. The city of Sendai and the surrounding farmland were devastated by the tsunami. The Japanese government is deploying hundreds of planes and ships in a relief operation. It has also requested some foreign search and rescue teams to help.
Matt, from Tokyo, writes: "I don't think these aftershocks have been reported enough. Each of these aftershocks have a bigger magnitude than the main quake felt in Tokyo."
The Onagawa nuclear power plant also suffered a fire in a non-nuclear turbine building, which took eight hours to extinguish, according to the World Nuclear Association. A minor fire burned in a non-nuclear service building of the Fukushima-Daini plant, but this was extinguished within two hours, the WNA added.
The pressure inside one of the six Boiling Water Reactors (BWRs) at the Fukushima-Daiichi plant has built up because the cooling system was damaged by the earthquake. The heat produced by the nuclear reaction inside the core still needs to be dissipated even after a shutdown. If the outage in the cooling system persists, eventually radiation could leak out into the environment, and, in the worst case, could cause a reactor meltdown, experts say.
The Kyodo news agency is now citing a safety panel as saying that the radiation level inside one of the reactors at the Fukushima-Daiichi nuclear plant is 1,000 times higher than normal.
Yet more large aftershocks as the sun rises off Japan's east coast. One registered 6.3 magnitude, the US Geological Survey said.
Meanwhile, officials in Washington have said the US military did not provide any coolant to a nuclear plant in Japan. Earlier, US Secretary of State Hillary Clinton said US Air Force "assets" had been used to do so.
Radiation levels at the damaged Fukushima-Daiichi nuclear plant are continuing to rise. The Jiji Press news agency says the levels are eight times above normal. Its report also cites a ministry official as saying there is a "possibility of a radioactive leak".
Prime Minister Kan has departed by helicopter to quake-hit north-eastern Japan.
The Tokyo Electric Power Company has said radiation may already have been released at the Fukushima-Daiichi nuclear plant.
Japan's Prime Minister Naoto Kan has just announced that residents living within 10km (6.2 miles) of the Fukushima-Daiichi nuclear station must evacuate their homes, according to the Kyodo news agency. Engineers are trying to fix the cooling system of one of the plant's reactors, which was damaged by the earthquake. The authorities had earlier told some 3,000 residents living within 3km (1.9 miles) to leave.
Back to California: The small fishing town of Fort Bragg has had its docks ripped apart and filled with debris by the tsunami,
the LA Times
Mexican officials have said high waves have hit their country's north-western Pacific coast, but that there were no reports of damage. Many ports have been closed, including Los Cabos and Salina Cruz, an important oil-exporting terminal.
Peruvian officials have said they are waiting until later on Friday to decide whether to evacuate low-lying coastal areas, including the port city of Callao.
Ecuador's President, Rafael Correa, has declared a state of emergency and urged residents to move inland. The area at risk includes the Galapagos Islands, home to many endangered species. The state oil company, Petroecuador, has also halted shipments.
US President Barack Obama has said the Federal Emergency Management Agency (Fema) is ready to come to the aid of any US states or territories which need help.
Tidal surges in the Hawaiian island chain were not much higher than normal, officials there said. There were no reports of injuries or severe inland property damage. However, low-lying areas in Maui were reportedly flooded and some coastal roads on Hawaii were swamped.
Ted Scott, a retired mill worker who lived in Crescent City, California, when a tsunami killed 17 people on the West Coast in 1964, told the Associated Press: "This is just devastating. I never thought I'd see this again. I watched the docks bust apart. It buckled like a graham cracker."
The tsunami swept out to sea at least five people watching the waves from the US West Coast. Four people were later rescued from the water off the coast of Oregon, but one man is still missing off northern California. The tsunami shook loose boats in that were not moved in time and tore apart wooden docks in at least two California harbours.
Our correspondent adds: "From there, the waves will roll on towards the Chilean coast, making landfall at about midnight local time (0300 GMT on Saturday). Some patients have been moved from low-lying hospitals and there are plans to evacuate thousands of people from the coast if necessary. The waves should have lost much of their intensity by the time they reach Chile - one expert has predicted they will be no more than 1m higher than normal. But with memories of last year's devastating earthquake and tsunamis still fresh in Chilean minds, the authorities are erring on the side of caution."
The tsunami is still fanning out across the Pacific Ocean and is due to hit the Chilean territory of Easter Island within the next few hours. The BBC's Gideon Long in Santiago says the authorities on Easter Island have already started evacuating people from the coast to the airport, which is 45m above sea level and should provide a safe haven. All civilian flights to the island have been cancelled. The tsunami is expected to hit at just before 1800 local time (2300 GMT), having travelled 14,000km across the ocean.
The official death toll from Friday's earthquake has risen to 184, Japanese police tell the Kyodo news agency. However, police in the city of Sendai have said separately that between 200 and 300 bodies have been found on the beach there. Kyodo estimates that more than 1,000 people have been killed.
The 6.7-magnitude earthquake which struck Niigata prefecture at 0400 on Saturday (1900 GMT on Friday) caused landslides and avalanches, police have said. The Kyodo news agency said there were no immediate reports of casualties after the tremor, which was followed by an almost equally strong one in the same area about 45 minutes later. The quakes struck in the west of the main island of Honshu, on the Sea of Japan coast.
David Abraham, a fellow at the Council on Foreign Relations based in Tokyo,
writes in the New York Times
: "Despite some serious damage in Tokyo, we were far more fortunate than those further north, who suffered a devastating tsunami in addition to the quake. As I reflect on the day's events, I have an eerie feeling that this was some sort of a trial run. Those of us in Tokyo, I fear, are still waiting for our big one."
tweets: "Still no word from family in Tokyo or Fukushima. #japan #fb"
US Coast Guard helicopters are searching for a man who was swept out to sea by powerful waves generated by the tsunami in Northern California, the Associated Press reports. Officials say the man was taking photos of the tsunami with two friends near the mouth of the Klamath river in Del Norte County. The two friends were able to get back to shore.
Kyodo also says the magnitude of the earthquake which struck Japan's mountainous Niigata prefecture early on Saturday morning has been revised up to 6.7.
Contact has been lost with four trains in Miyagi and Iwate prefectures, Japan's official Kyodo news agency reports.
Nick Gunn in Chiba, Japan, writes: "All children and staff at Makuhari International School safe despite severe quake. Around 6O pupils and adults stranded in school overnight but comfortable and in relatively good spirits. Aftershocks every few minutes continuing throughout the night."
The World Nuclear Association said pressure inside the containment of Reactor 1 at Fukushima-Daiichi had been steadily increasing over the time that its emergency core cooling systems had not been active. The Tokyo Electric Power Company reported at 0200 local time (1700 GMT) that pressure had increased beyond reference levels, but was within engineered limits, the WNA added.
Three to four new power supply cars have arrived at the Fukushima-Daiichi nuclear plant in north-eastern Japan to provide emergency electricity for the earthquake-damaged cooling system of one reactor,
the World Nuclear Association has said
. The power cars are being prepared for connection, the WNA said, citing the Japanese ministry of economy, trade and industry. Other power modules are being flown in.
The Japanese ambassador to the UK, Keiichi Hayashi, has told the BBC it is impossible to impossible to estimate the number of dead at this stage: "We are still in the process in the process of determining what happened and it looks like there are a number of missing people in addition to the number of victims that we have so far counted. It is not just Japanese nationals about whom we are concerned. There are nearly 20,000 British nationals in Japan, but I have not heard of any casualties among UK nationals."
Pope Benedict XVI was "deeply saddened by the brutal and tragic consequences of the severe earthquake and tsunami that struck north-eastern coastal regions" of Japan, a telegram sent by Cardinal Tarcisio Bertone on his behalf to Japan's Roman Catholic bishops says. The pope was praying for the dead and hoped that their families and friends would find "strength and consolation", it adds.
provided by the US National Oceanic and Atmospheric Administration (NOAA) shows the intensity of the tsunami caused by the earthquake which struck Japan.
Ben Hentschel in Tokyo
tweets: "can't sleep. earthquakes the whole night... its 4:30am right now... just can't close my eyes"
The 8.9-magnitude earthquake which struck Japan on Friday was the strongest in the area in nearly 1,200 years, David Applegate, a senior science adviser at the US Geological Survey, tells the Associated Press. He says the quake ruptured a patch of the earth's crust 240km (150 miles) long and 80km (50 miles) across.
California Governor Jerry Brown has said he has directed the state's emergency management agency (Cal EMA) to make state resources available to the Japanese government. "We stand ready to assist them", he added. Mr Brown also urged Californians to heed tsunami warnings.
mayu in Tokyo
tweets: "Earthquake is still going on. Such a crazy day today. Furious nature..."
In the Indonesian capital Jakarta, the BBC's Kate McGeown says that the very word tsunami triggers memories of the devastating wave that struck in 2004, killing 170,000. But the tsunami warning there has now been lifted, she says.
There have been no reports of damage so far from the new quake. There have been dozens of aftershocks following the main quake more than 13 hours ago, but this one is in a different location.
Kyodo News reports that no fresh tsunami alert has been issued after the latest quake.
More from NHK on that new quake: It struck Japan's mountainous Niigata prefecture in the west of the main Honshu island at about 0400 Saturday (1900 GMT Friday), the broadcaster says.
Japanese broadcaster NHK says the latest quake was centred in north-west Japan.
A magnitude 6.6 quake has now struck in central Japan, AP news agency reports, causing Tokyo buildings to sway. It is not clear if this is connected to the earlier quake and aftershocks. More on this as we get it.
The BBC's Rajesh Mirchandani in Los Angeles says there have been evacuations around Crescent City in northern California. However, along the Santa Monica coast many people are using the opportunity to go and look at the waves.
Our correspondent in Tokyo adds that although the military has already discovered some scenes of destruction, it will not be until first light that the true scale of that disaster will become clear.
The BBC's Roland Buerk, in Tokyo, says many people in the city are spending the night in their offices. Millions more chose to walk home because trains were suspended. However, crowds have been pretty orderly and calm, he adds.
More on the troubled nuclear plant: Japan's trade minister, Banri Kaieda, says authorities are nearing a decision to release radioactive steam from the Fukushima nuclear reactor in a bid to ease a build-up of pressure, AFP reports. Thousands of local residents have been evacuated.
ABC's Christiane Amanpour
tweets: "Coolant for compromised nuclear plant in #Japan is simply water. Diesel generators sent in to get water pumps running."
The situation at the nuclear reactor at Fukushima seems to be worsening. Japanese authorities are now to release radioactive vapour to ease pressure, AP news agency reports. Engineers are trying to fix the cooling system to the main reactor, damaged in the quake.
The power of the earthquake off north-east Japan shifted the earth's axis by nearly 10in (25cm),
citing the National Institute of Geophysics and Vulcanology. The phenomenon is not unusual for a major quake.
Boats in Santa Cruz harbour, California, have been damaged by waves generated by the tsunami,
US broadcaster ABC reports.
Water levels dropped by about 9ft (2.7m). Cliffs above Ocean Beach in San Francisco have been filled with spectators, it says.
Some reports from local US media of the tsunami's arrival on the US West Coast:
Joe Vazquez from CBS5
tweets: "Second tsunami surge now hitting Santa Cruz. CBS5 reporting a dozen or so sunken boats. County spokesman says at least $2m damage."
tweets: "Crescent City OES: All docks are gone after first surge, 35 boats crushed, water starting to fill harbor parking lot."
Just a reminder that large aftershocks of around magnitude 5.0 are continuing in north-east Japan, more than 12 hours after the devastating 8.9 quake. Stay with us for further live updates.
The BBC's Roland Buerk in Tokyo says the official death toll has risen to 350, with another 500 or so missing.
The BBC News website has published a large
map of Japan with embedded video
from key locations, showing the devastation caused by the earthquake and tsunami.
President Barack Obama says the US is ready to give Japan any assistance it needs to stabilise the nuclear reactor in Fukushima. Officials have said pressure is rising after a cooling system failure.
Scientists have said the earthquake ranked as the fifth-largest in the world since 1900 and was nearly 8,000 times stronger than one that devastated the city of Christchurch in New Zealand last month. "The energy radiated by this quake is nearly equal to one month's worth of energy consumption" in the United States, Brian Atwater of the US Geological Survey told the Associated Press.
Ali Attas, a Kenyan journalist living in Yokohama, has told the BBC's Focus on Africa programme about the moment the earthquake struck: "It was just an incredible scary feeling, the intensity started increasing. When I started moving in the room, I could not stand on my feet. I was beginning to hit the wall... I am not going to sleep tonight." Balkisu Saidu, a Nigerian studying in central Tokyo, said she had been standing in a queue for a bus for nearly three hours, trying to get home.
All Japanese ports have reportedly been closed. "It's a big mess. All discharge operations are suspended in the area," a Japanese ship broker told the Reuters news agency. Another broker said: "Most or all coal stocks will be washed out at many of the coal-fired power plants. Ports will be closed at least for a short time until damage assessments can take place."
A 50cm-high (20in) tsunami has awept along Mexico's north-west coast, AFP reports.
President Obama's statement concludes: "Today's events remind us how fragile life can be. Our hearts go out to our friends in Japan and across the region, and we are going to stand with them as they recover and rebuild after this tragedy."
He adds: "Tsunami warnings have been issued across the Pacific. We have already seen initial waves from the tsunami come ashore on Guam and other US territories, on Alaska and Hawaii, as well as along the West Coast. Here in the United States, there hasn't been any major damage so far. But we are taking this very seriously and we are monitoring the situation very closely. Fema is fully activated and is co-ordinating with state and local officials to support these regions as necessary. Let me just stress: if people are told to evacuate, do as you are told."
Mr Obama says that during a telephone conversation with Prime Minister Naoto Kan he conveyed the American people's "deepest condolences, especially to the victims and their families". "I offered our Japanese friends whatever help is needed," he adds. "We currently have an aircraft carrier in Japan and another is on its way. We also have a ship en route to the Marianas Islands to assist as needed. The defence department is working to account for all our military personnel in Japan. US embassy personnel in Japan have moved to an off-site location, and the state department is working to account for and assist any and all American citizens who are in the country."
US President Barack Obama says the United States has an aircaft carrier already off the coast of Japan and another is one its way.
The first waves from a tsunami caused by the Japanese earthquake have reached the US mainland along the Oregon coast. The waves were expected to come ashore over a period of several hours, with the highest and most powerful expected at 0930 (1730 GMT), Geophysicist Gerard Fryer at the Pacific Tsunami Warning Center in Honolulu said high water reached Port Orford at 0730 (1530 GMT). Officials along the coast activated warning sirens hours earlier to alert people to leave low-lying areas.
Waves generated by the tsunami can be seen lapping at Ocean Beach in San Francisco on this
The celebrity chef, Ken Hom, was staying at a hotel in Tokyo when the earthquake struck. He told the BBC: "We're getting a lot of tremors; they are coming every 15 minutes and the room starts shaking and it's pretty scary, especially when you're on the 20th floor. When the earthquake struck I was in the pool with my partner and the whole thing started rocking, as if you were in the sea. We looked at each other and said: 'This is the big one,' because we have lived in California and we had experienced a small earthquake two days ago in Tokyo. It was really interesting because the whole building seemed to creak, but nothing fell or we did not feel in danger. And after it stopped the pool continued to rock for at least 15 minutes."
Jarrod Lentz, who lives in Tokyo, writes: "The authorities have allowed us to return to our flats. Some people tried to go out and buy food, but found supermarkets were closed. I do not know what to do next. My employers haven't told us to evacuate yet. There is no electricity, water or gas. I'm still bewildered by the fact that the sheer shock of the earthquake made the concrete road outside my window rippled." He also took
of a displaced manhole cover.
A second train has been reported missing following the quake and tsunami in Japan, according to the AFP news agency.
The BBC's Mark Kinver has written an
article explaining the "nuclear emergency"
declared by Japan's prime minister. The reactors at the Fukushima-Daiichi power station are Boiling Water Reactors (BWR), he says. Heat is produced by a nuclear reaction in the core, causing the water to boil, producing steam. The steam is directly used to drive a turbine, after which it is cooled in a condenser and converted back to water. The water is then pumped back into reactor core, completing the loop. Even when the reactor is shut down and the nuclear fission is halted, an intense level of heat remains and needs to dissipated, which is the role of the cooling mechanisms.
Nuclear physicist Dr Walt Patterson tells the BBC it sounds like there is a "serious problem" at the Fukushima-Daiichi plant. "It's the sort of thing that nuclear engineers have nightmares about," he says. "If it is not resolved in the next few hours it will get serious. If the core is uncovered, then those rods at the top may get hot enough to melt themselves."
The Tokyo Electric Power Company has said the pressure inside the No. 1 reactor at its Fukushima-Daiichi nuclear plant has been rising, with the risk of a radiation leak, according to the Jiji Press news agency. Tepco planned to take measures to release the pressure, the report added. The reactor's cooling system began to malfunction after the earthquake. People living close to the plant were later evacuated as a precaution.
The death toll from the earthquake and tsunami is expected to exceed 1,000, Kyodo adds.
Kyodo also reports that the death toll from the earthquake has been revised down by police from 137 to 133. Another 531 people are missing.
Japanese defence ministry officials tell the Kyodo news agency that 1,800 homes in Fukushima prefecture have been destroyed.
Virgin Atlantic has said it has not made a decision on whether its daily London-Tokyo service will operate on Saturday or Sunday. Earlier, we cited a Press Association report which said that the service had been cancelled.
The World Bank has said it is "ready to help" Japan after the earthquake and tsunami, the AFP news agency reports.
A tsunami "advisory" has been issued in Canada's western province of British Columbia. The government said the tsunami might "potentially produce strong currents dangerous to those in or near the water". It could "impact marinas and other coastal infrastructure or create strong currents in harbours and isolated coastal areas", the statement added.
Tsunami warnings have been lifted for mainland Australia and New Zealand, officials say. China, Indonesia and the Philippines lifted their tsunami alerts after Taiwan and the US territory of Guam also said the threat of the massive waves had passed. Warnings remain in effect for several countries including Mexico, Guatemala, El Salvador, Costa Rica, Nicaragua, Panama, Honduras, Chile, Ecuador, Colombia and Peru.
China is ready to send rescue and medical teams to Japan, a foreign ministry spokeswoman has said. Jiang Yu said the Chinese government was greatly concerned and expressed deep sympathy to Japan for the casualties and major losses of property caused by the earthquake and tsunami, according to the Xinhua news agency.
Aftershocks are continuing in Japan. Another six - one with a magnitude of 6.1 - have recently shaken the country's north east, the US Geological Survey reports.
The UK ambassador to Japan, David Warren, has told the BBC that his concern is with helping any British nationals caught up in the disaster: "We're in touch with the local authorities, as well as with central government, to try and identify and assist as many British people as possible. We are not aware at the moment of any British casualties but of course we're keeping the situation under very close review."
The BBC's Roland Buerk in Tokyo says a US aircraft carrier could be deployed off northern Japan to help with firefighting and the rescue effort. Officials in Tokyo say it is one of a number of ideas being considered.
Japan's Kyodo news agency is now saying the death toll has risen to 137, with 531 people missing.
In Waikiki, tourists were moved into the upper floors of hotels and the cliff at Diamond Head became a safe spot for watching the waves come ashore, Hawaii News said. Civil defence officials were quick to remind residents that inundation effects could continue for several hours and to stay away from evacuation areas.
Reports from Hawaii say the island chain has been spared any major damage by the tsunami. When the tsunami arrived on Oahu at about 0330 local time, it surged onto beaches and up canals, exposing reefs, Hawaii News reported. According to the National Weather Service, the biggest wave measured so far was 85cm (2.8ft) at Hanalei, on Kauai. The wave action is expected to continue and for waves to grow in height.
Tokyo worker Patrick Bosso tells the BBC it looks like he and his colleagues will be stranded in their office tonight. "Trains are not working yet and they are still trying to check the tracks that everything is OK," he says.
US Secretary of State Hillary Clinton says the US Air Force in Japan has transported coolant to the plant. Officials say the facility should be back to normal soon.
Meanwhile, the World Nuclear Association has said it understands the situation at the Fukushima Daiichi nuclear plant is "under control", and that water is now being pumped into its cooling system. The Japanese government earlier declared an emergency as a precaution and evacuated people living nearby, after there was a malfunction and the water level began to fall. A WNA analyst said the back-up battery power system was now online.
Kyodo also reports that US President Barack Obama has offered support to the Japanese government and people in a telephone conversation with Prime Minister Naoto Kan.
The death toll from the earthquake in Japan has now risen to 117, police tell the official Kyodo news agency.
Survivors have been talking about the moment the earthquake struck Tokyo. Timo Paul, who lives in a block of flats on the outskirts of the Japanese capital, was on the telephone with his wife. He told the BBC: "When it really started to get quite seriously shaking, at that point I just thought I could possibly die. I didn't know if I could get down the stairs in time to reach the bottom floor and then I also had my wife screaming in my ear because she was working in one of the buildings in Tokyo and she was desperately trying to get out of the building as well."
The first waves from the tsunami have reached the US mainland along the coast of Oregon, the Associated Press reports.
Civil defence officials in the Philippines have now lifted the tsunami warning covering its Pacific seaboard, President Benigno Aquino's spokesman says.
A dam in Japan's north-eastern prefecture of Fukushima broke, creating a torrent of water that washed away homes, the Kyodo news agency reports.
Another two aftershocks measuring 5.1 magnitude have just shaken Japan's east coast, the
US Geological Survey
New York Times
has a new gallery of striking images showing the aftermath of the Japanese quake and tsunami.
The United States appears to be out of major danger from the tsunami, White House Chief of Staff Bill Daley has said. "The tsunami wave has gone through Hawaii and there does not seem to be any enormous impact, which is extremely encouraging," he told a meeting of the President's Export Council in Washington. There was still some risk to the US West Coast, "but I think the enormous fears that that were there hours ago, for some of us hours ago, has diminished greatly, which is quite a relief for all of us", Mr Daley added.
UK Foreign Office is now advising
that all UK nationals worldwide who are concerned about the safety of friends and relatives in Japan should call the British helpline number +(44) 207 008 0000. They should no longer call the British embassy in Tokyo or the consulate-general in Osaka.
An update now on the nuclear power station in Japan at the centre of a huge evacuation order: Officials have said the reactor cooling system that failed after the quake at the Fukushima Daiichi nuclear plant is expected to return to normal soon, according to the Jiji Press news agency. Thousands of residents were evacuated as a precaution.
All weekend matches in the Japanese football league, the J-League, have been postponed and other professional sports have been put on hold, the Associated Press reports. A special committee meeting investigating match-fixing in sumo wrestling has also been delayed.
Indonesia has lifted its tsunami warning after only small waves reached its eastern coastline and caused no damage, Japan's Kyodo news agency reports. The Indonesian meteorology agency said waves of only 10cm were observed in North Sulawesi's port of Bitung and the island of Halmahera, in North Moluccas Province. Thousands of people earlier fled their homes.
The Japanese military is readying 300 planes and 40 ships to assist the rescue operation, according to the Kyodo news agency.
The BBC News website has now published a
on the Japanese earthquake and tsunami.
US state department spokesman Philip Crowley has said its officials "have been in touch with the Japanese government and we stand ready to provide whatever assistance needed in response to the tsunami". He also said ambassador John Roos had moved the Tokyo embassy's command centre to an alternative location due to the "many aftershocks" in the capital.
Queen Elizabeth II has sent a message of sympathy to Emperor of Japan following the massive earthquake and tsunami. "I was saddened to hear of the tragic loss of life caused by the earthquake which has struck north east Japan today. Prince Philip joins me in extending our heartfelt sympathy to your majesty and the people of Japan. Our prayers and thoughts are with everyone who has been affected by the dreadful disaster."
Another five powerful aftershocks measuring around 5.5 magnitude have just rattled the eastern coast of Japan in quick succession, the US Geological Survey reports.
Houses and other buildings are also ablaze across large swathes of land in Kesennuma city in Miyagi prefecture, near Sendai, footage broadcast by Japanese TV shows. The city has a population of 74,000.
More on the travel disruption caused by the earthquake: Virgin Atlantic has said its daily London-Tokyo service will not operate on Saturday or Sunday, the UK's Press Association reports. But British Airways is scheduled to operate one flight to Narita and one to Haneda on Saturday.
A large waterfront area near Sendai, the city closest to the epicentre, is on fire, Japanese TV is reporting.
Back to Japan now: The official Kyodo news agency is reporting that about 88,000 people are missing.
a reporter for US news channel KGW, is travelling along the Oregon coast. He tweets: "Gas stations busy along coast, people in seaside gathered at elementary school on higher ground"
Earlier, the tsunami reached the Philippines, but did not cause any damage. Renato Solidum, head of the Philippine Institute of Volcanology and Seismology, said that waves ranging from 30cm to 70cm were recorded in five provinces facing the Pacific Ocean between 1800 and 2000 local time. He warned that more might follow, although they would be smaller. Tens of thousands of people living in coastal areas were earlier evacuated to higher ground.
Meanwhile, Oregon's emergency management agency has advised residents of coastal areas to evacuate before 0700 local time (1500 GMT) due to the risk of a tsunami. But a spokeswoman told the Reuters news agency that no-one was being forced to leave. She said schools along the coast would be closed, and that the National Guard was on standby.
The BBC's Heather Maclean, who is holidaying in Kauai, says: "We were staying on the south shore of Kauai, at a resort in the town of Poipu, right on the coast. We were evacuated about five hours ago and told to go to high ground. We are now at a community college about 10 miles (16km) inland, north of Poipu. We are waiting to see what happens. Meanwhile, the roads are closed."
Mary Vorsino in Hawaii
tweets: "At Diamond Head lookout, waves receded twice, showing exposed reef. The water then came back in, but didn't appear too high."
Waves at least 0.9m (3ft) high have been recorded on the Hawaiian islands of Oahu and Kauai. Officials have warned that the waves will continue and may become larger.
President Barack Obama was woken at in the early hours of the morning to be told about the Japanese earthquake and tsunami, the BBC's Steve Kingstone in Washington says. Much of the US west coast, as well as Hawaii, remains on tsunami alert.
Four more large aftershocks have just rattled the east coast of Japan, the
US Geological Survey
reports. They ranged in magnitude from 5.1 to 5.8.
He adds: "Japan is one of the most generous and strongest benefactors, coming to the assistance of those in need the world over. In that spirit, the United Nations stands with the people of Japan and we will do everything and anything we can at this very difficult time. We will be watching closely as the aftershocks are felt across the Pacific and South-East Asia throughout the day. I sincerely hope that under the leadership of Prime Minister Naoto Kan and the full support and solidarity of the international community, the Japanese people and government will able to overcome this difficult time as soon as possible."
Mr Ban says: "The world is shocked and saddened by the images which we saw this morning. On behalf of the United Nations, I want to express my deepest sympathies and heartfelt condolences to the Japanese people and government, and most especially to those who have lost family or friends in the earthquake or subsequent tsunami."
UN Secretary General Ban Ki-moon expresses his condolences to the Japanese people and government. He says the UN will do anything it can to assist.
Japan's government has declared an emergency situation at the Fukushima Daiichi nuclear plant after a reactor cooling system malfunction. But officials say there is no radiation leaking. Some 3,000 residents living near the plant in Fukushima prefecture, north of Tokyo, have been told to evacuate the area.
UN Secretary General Ban Ki-moon is due to make a statement on the earthquake and tsunami in Japan.
The US state department is advising US citizens to avoid all non-essential travel to Japan following the massive earthquake.
Ms Byrs says the OCHA has 62 search-and-rescue teams on standby, ready to be deployed should the Japanese government need their assistance. "Japan told us they are, for the moment, assessing the situation and they have put their full forces into the response. So we need a request from them now; we need the green light," she adds.
The spokeswoman of the UN Office for the Co-ordination of Humanitarian Affairs (OCHA), Elisabeth Byrs, tells the BBC that it is doing all it can to help Japan. "We have been in close contact with the Japanese emergency response team, and more precisely with the director of the Japan disaster relief team, since the very beginning. We have activated our operation centre and we have put on high alert all our regional offices in Japan, Kobe, and also in Bangkok, Thailand, for Asia and Pacific."
Traffic is heavy on US Route 101 along the Oregon coast near Florence, as people evacuate low-lying areas to avoid the tsunami crossing the Pacific, the Associated Press reports. Sirens have sounded, warning residents to move to higher ground.
Japanese police have now confirmed that between 200 and 300 bodies have been found on the beach near Sendai, the closest city to the epicentre. NHK television said the victims appeared to have drowned. Earlier, police said at least 60 people had been killed and 56 were missing.
The BBC's Heather Maclean, who is holidaying in Hawaii and has been evacuated to higher ground, says radio is reporting a 2m (6ft) wave has hit beaches in the south and people are waiting to see if further waves arrive.
Ryan McGuinness on the Hawaiian island of Maui tells CNN that he is standing about 10ft away from the shore. He says there have been surges, during which the sea has advanced about 20ft further inland than normal. But now, he says, the sea level has receded about 200ft, exposing reefs and rocks which are normally always covered. People are calm, he adds, but they are now moving to higher ground.
Local television stations in Hawaii are broadcasting footage of the first signs of the tsunami.
Dr John Elliott, an earthquake expert at Oxford University, has told the BBC that Japan has so far coped well with such a huge quake. "They have had many earthquakes in their history and they have learned from this and they build appropriately for it," he said. "The tsunami is much harder to deal with. They have hundreds of kilometres of coastline and low-lying areas and it is hard to mitigate against the direct effect of such large event."
California emergency management agency spokesman says the tsunami could generate waves of up to 6ft (1.8m) when it hits parts of the state's northern coast. "It is very possible there may be some evacuations here," Jordan Scott tells the Reuters news agency. He added that the area near Crescent City, not far from the border with Oregon, was likely to see biggest waves.
Large aftershocks are still continuing off Japan's east coast. The
US Geological Survey
reports seven more over the past half hour measuring between 5.2 and 5.6 magnitude.
There has also been a major explosion at a petrochemical complex in Sendai, according to the Kyodo news agency.
Between 200 and 300 bodies have been found on a beach near Sendai, the semi-official Jiji Press news agency is reporting.
Residents of coastal areas of Hawaii have been evacuated to refuge areas at community centres and schools, while tourists in Waikiki have been moved to the highest floors of their hotels, according to the AP.
Tsunami waves have now reached the Hawaiian island chain. The PTWC said Kauai was the first island hit. Officials predicted Hawaii would experience waves up to 2m (6.6ft).
A passenger train is unaccounted for in a tsunami-hit coastal area of Japan, the AFP quotes a report on the Kyodo news agency.
Zeina Talhouni, a tourist in Tokyo, tells the BBC World Service that the city is now "at a standstill. It is quite surreal". She says it took her three hours to get home to the suburbs from the city centre.
More on Indonesia now. The waves that are hitting the north-east of the country are under half-a-metre - so not likely to cause substantial damage, the BBC's Kate McGeown says. Most people though have moved to higher ground just in case, and there could be more waves to come.
William Ramsay in Tokyo says: "I've been walking for hours, getting home. The streets are packed with people walking home as there's no transport. I've never seen anything like it in Tokyo. Some of these people will be walking for 20km. The mobile networks are down."
UK Foreign Secretary William Hague says the earthquake and tsunami in Japan are "of huge dimensions by any standards". He says Britain is ready to send humanitarian assistance or search and rescue teams to Japan in the coming days.
And minor waves have now begun hitting the Philippines, the country's chief seismologist is quoted as saying by the AFP.
A small tsunami has just hit the northern coast of Indonesia, the BBC's Kate McGeown in Jakarta says. It is unclear how much damage it has caused and people are still on alert because there could be more waves in the coming hours.
Timo Paul, who lives in the ourskirts of Tokyo, writes: "The buildings here seem okay, but we don't have any working water at all, so we think one of the water pipes must have broken. I've also seen an area where it looks as though the cement has liquified. There are some large factories nearby and some are on fire."
The BBC's former Japan correspondent Charles Scanlon says that while the government has set up an emergency task force in Tokyo, it will be difficult for rescuers to get to the affected region. He says: "They problem is they've got to get to this relatively remote area, especially the province of Iwate, to the north of Sendai - an area where we've seen some television pictures showing a town almost completely levelled by the earthquake. It is dark now, it's going to be very cold, it's still winter and snow is forecast."
Japanese authorities are urging some 2,000 residents living within a 2km radius of a nuclear plant in Fukushima to evacuate, the AFP reports. The plant has been shut down after its cooling system failed.
The death toll has now risen to 60, the Associated Press is quoting Japanese police as saying.
Simon Boxall, from the
National Oceanography Centre
in Southampton, explains how a quake triggers a tsunami: "An earthquake with the epicentre on the seabed rather than inland is a bit like throwing a huge boulder into the water." Mr Boxall tells the BBC World Service that as a result the waves moving away from the epicentre "move incredibly fast, in fact in the deep water they move at 800kmh. But as they get to shallower water, the front of the waves slows down, the back of the waves keep going at full speed. So what starts off as a ripple that may only be 20 or 30 cm high ends up with a wave that piles up to an eccessive 10 metres. That is what happened here. And of course this part of north-east Japan is very low-lying, so it's become swamped incredibly quickly."
PRwahine in Hawaii
tweets: "Hard to describe the feeling of waiting to know if all my belongings will soon be limited to what is in my car."
The tsunami is expected to reach Mexico's coastline within three to four hours, the BBC Mundo's Alberto Najar reports. Ports in the state of Guerrero are now closed. In Baja California Sur, civil protection authorities say they expect no major damage.
Ecuador has now ordered preventive coastal evacuations, the AFP reports.
BBC's Kate McGeown in Indonesia says a tsunami has been detected in the north east of the country, but it's only half-a-metre high. Too early to say if damage has been caused.
Japanese police now say that at least 40 people were killed and 39 are missing after the earthquake and tsunami.
Auckland-based geologist Chris Buckley tells the BBC World Service the tsunami wave is on its way towards New Zealand at 500 or 600 miles an hour. "It's kind of like looking at an express train heading towards us right now", he says.
Some people in Hawaii are now using the hashtag
to talk about the tsunami alert.
in Honolulu tweets: "Water sold out by second siren at Mililani Wal-Mart. Bread shelves bare."
The BBC's Greg Ward in New Zealand says authorities have downgraded the tsunami threat. They say there is now a marine threat only. This means strong and unusual currents are possible in the sea, river mouths and estuaries, but no land threat is expected, our correspondent says.
tweets: "Gov't taking precautionary measures for Fukushima I nuclear power plant. No radioactive leakage. No need for residents nearby to evacuate."
Reuters quotes a report on Japan's Kyodo news agency which says that a ship carrying 100 people was swept away by the tsunami.
The BBC's Kate McGowen in Jakarta says people in the north-east of Indonesia are waiting for the tsunami to hit the coast there any moment now. She adds: "This is not the region that was hit by the tsunami in 2004. But when you mention the word "tsunami" here, people in Indonesia know the scale, they know how massive this could be. We have been hearing about traffic jams in the main towns and cities in North Sulawesi as people try to leave the coast as quickly as possible."
Mike Hall in Hakodate, south of Hokkaido, writes: "We have been really lucky, my apartment was shook up for several minutes and a few things fell over but there was no major damage. It is very much like a swaying rolling motion, with jolts that really put the fear of God in you. Initially, I didn't pay any attention as we've had earthquakes before. But this time, it went on for longer and there were several big aftershocks. Power and water supplies are fine at the moment and cell phones and the internet seem unaffected. But we have a major tsunami warning in effect."
The BBC's Roland Buerk in Tokyo says 32 people are now known to have died in the earthquake and tsunami. Our correspondent adds: "There are enormous crowds of people on the streets of Tokyo, the roads are clogged with traffic, and millions of people are walking home because the railways have been closed down. But it is calm and orderly. People are still queueing at pedestrian crossings.
A number of countries in the Pacific are now bracing for a tsunami. George Pillioco, who lives in Vanuatu, tells the BBC: "The radio told us to expect the tsunami between 2300 and 0100 tonight (1200-1400 GMT), and that we should be prepared. We're on the east of the island which is on a hill. So, we're not going anywhere, but of course we're worried".
US President Barack Obama offers his "condolences" to the people of Japan and says his country stands ready to help them after a massive earthquake and tsunami, the AFP reports.
The British Geological Survey tells the BBC that the Japanese earthquake is the 6th largest ever recorded (i.e. since 1900).
Japan has declared a state of emergency because of the failure of the cooling system at one nuclear plant, according to the Associated Press. Officials say there has been no leak of radiation.
BBC1 is now broadcasting a half-hour special on Japan's quake and tsunami.
Britain's Foreign Office has now set up a helpline for anyone in the UK worried about friends or relatives in Japan affected by the earthquake and tsunami: 020 7008 0000.
Roland Pease from the BBC Science Unit says: "I doubt scientists have ever had images like this showing the waves of water and debris, and they will be looking at them closely to find out more about these events."
Stuart Weinstein, from the PTWC, tells the BBC World Service that coastal areas of Hawaii have been evacuated. He says Hawaii could be hit by a wave of up to two-metre high. He adds: "For South America, we are looking right now at a height of between half-a-metre and a metre, for some places on the US West Coast it might be around a metre."
tweets: "NHK showing massive cracks in pavement, extensive external building damage in Sendai."
Shola Fawehimni, who is at Hokkaido's airport in northern Japan, says: "It was a bit surreal. The chairs and the floor started moving and swaying. I wasn't really sure what was going on. Then the building started swaying and I realised it was an earthquake. Some ceiling panels fell down."
The UN nuclear watchdog, the IAEA, says four nuclear power plants closest to the earthquake's epicentre have been shut down safely.
UK Prime Minister David Cameron says the Japanese earthquake is a "terrible reminder of the destructive power of nature. Everyone should be thinking of the country and its people, and I have asked immediately that our government look at what we can do to help."
The BBC News website
now runs a piece where eyewitnesses recount their experience of the moment the quake struck.
The Japanese government and police raise the death toll from the quake to 29, the Associated Press reports.
The authorities in Taiwan say there have been small evacuations, but no major damage and no unusual sea waves, the BBC's Cindy Sui in Taipei reports.
tweets: "There were reports about mudslides in mountains. No safe places in japan..."
Louisa Ke, a BBC reporter in Tokyo, says: "When the earthquake happened, I was in my study.The earthquake lasted three minutes, according to reports, but it felt like five. This is something I have never witnessed in my life.
A tsunami warning is now extended to the entire US West Coast, according to the Associated Press.
tweets: "Thoughts are with the people of Japan and all the neighbouring countries that will be affected by the tsunami."
The death toll from the quake has now reached 26, the AFP is quoting reports in Japan's media.
More from a news briefing in Tokyo by Japan's meteorological agency. Spokesman Hirofumi Yokoyama said: "Historically, the magnitude scale was different, so simple comparison is not possible - but 8.8 is one of the largest we have experienced in Japan... It is the largest recorded by the equipment currently in place". He added that 8.8 magnitude "is maximum, unprecedented scale looking through history".
Japan's meteorological agency now says earthquake had a magnitude of 8.8.
The earthquake which hit Japan on Friday was the country's biggest ever and the seventh largest on record, according to US Geological Survey data, the AFP reports.
Jeffrey Balanag, who lives in Tokyo, describes the moment the quake struck. "The building wasn't shaking it was rolling, like a boat on the sea. It was really creepy. It made me very scared," he tells the BBC.
The confirmed death toll now stands at six, the BBC's Roland Buerk in Tokyo says.
The Red Cross warns that the tsunami wave caused by the quake is currently higher than some Pacific islands and "could go right over them".
Reports now say at least five people died and many are missing.
Robert Cessaro, from the PTWC, tells the BBC World Service that "the depth of the quake is about 10km, in other words it's a very shallow event, and also it's in the water. So right away we know that it's going to produce a tsunami. This one is pretty big."
In the Philippines, the government strongly urged residents of the country's Pacific coast to "go farther inland" because of a tsunami threat, the AFP reports.
Reports now say that at least one person was killed in Tokyo and there were several injuries in the capital.
Natsuki Morikubo, another Tokyo resident, tells the BBC: "Suddenly the ground started to shake and I thought I felt sick or something, but I gradually realised this was the huge one we expected for years."
One Tokyo resident, Yukiko, told BBC World Today she was in her fourth floor apartment when the quake struck: "I first thought it was just the usual moderate quake we have from time to time. Then it started shaking really violently. I've always lived in Tokyo, but I've never felt such a big quake in my life.
Victor Sardina, from the PTWC, says that a "tsunami wave will cross the Pacific, no doubt about that. The same tsunami wave will reach all the way down to Chile... This is going to produce a huge amount of damage."
The Pacific Tsunami Warning Center (PTWC) in Hawaii widens its tsunami warning to include Hawaii and the rest of the Pacific Ocean. The warning also includes Australia, New Zealand, Mexico and Central and South America.
Japan's Chief Cabinet Secretary Yukio Edano says troops are being sent to help in the affected areas. "We have already had offers of help from foreign countries, we are prepared to ask for relief in the future," he adds.
In Russia's Far East, some 11,000 people have been evacuated from areas that could be affected by the tsunami, including the Kuril islands and Sakhalin island
The earthquake struck at 1446 local time (0546 GMT) and was followed by a series of powerful aftershocks. Seismologists say it is one of the largest quakes to hit Japan for many years.
"Damage has been inflicted over a wide area," Japanese Prime Minister Naoto Kan says. "I offer deepest sympathy to people affected by the disaster. Some nuclear plants have stopped automatically, but no information about any leaks of radiation. We ask people of Japan to act calmly."
The BBC's Roland Buerk in Tokyo says: "Buildings swayed... I was in the street, it was like walking across the deck of a ship at sea. People were shocked, some dropped to the ground in fear".
Japan's NHK television showed cars, ships and even buildings being swept away by a vast wall of water. Numerous casualties are feared, and there have already been reports of injuries in Tokyo.
Officials say the 8.9 magnitude quake struck off Japan's north-east coast, about 250 miles (400km) from Tokyo at a depth of 20 miles.
Welcome to the BBC's live coverage of events in Japan, where a massive earthquake has triggered a devastating tsunami. Stay with us for the latest updates - reports from our correspondents on the ground, expert analysis, eyewitness reports and reaction from around the world. You can contact us via email, text or twitter. We'll publish what we can.