Strong aftershocks have continued in northern Japan two days after 24 people died in the country's worst earthquake in almost a decade.
No fatalities have been reported after the latest quake which measured 5.6 in magnitude.
Much of the affected region is without power and authorities say there is a desperate need for food and water supplies.
The Japanese meteorological agency has also warned that more quakes are likely in the near future as well as several days of heavy rain.
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I along with my wife live on the ground floor of an eight storey building. We were making curry for the coming week. Just after the first shaking, we stopped gas line and opened the door. We were about to jump to the garden, watching our nearest building also shaking. It looked like an array of lights trembling.
Biswajit and Muna, Misato, Saitama
My boyfriend is staying at a scientific conference about 200km south of the epicentre and when I returned from a camping trip in Wales on Sunday evening I phoned him and the first I heard of the earthquake was him saying "Oh no, the ground is shaking again." Although he was fine, it was still quite frightening. He has been in Japan only three weeks and experienced two earthquakes and two typhoons; it makes you realize how brave people in Japan have to be all the time.
This is the biggest earthquake I've experienced since living in Tokyo. Even though Tokyo was measured at No 3 it still shook quite violently. I was teaching at my kids' class when Saturday's earthquake hit... My wife's family lives in Niigata so, naturally we were really worried. Is Tokyo next for the big one?
Matt, Tokyo, Japan
I was on the ninth floor of hotel in Tokyo when the earthquake struck. I have felt tremors here before, but not like this. Unlike other tremors I have felt, this one kept going and going. For a brief moment, I was not sure if the building would withstand the shaking.
Brian MacCarthy, Tokyo, Japan
Because of the noises heard almost all evening above our heads caused by helicopters carrying food and water, most of us have spent two helpless nights since the biggest ever earthquake hit our neighbourhood. Fortunately, none of my family nor friends were injured by the first tremors, but our two children (mature enough to sleep by themselves) insisted on sleeping in the same bed with us, asking timidly (dad, please, only tonight) if they could keep on holding our hands as they went to bed. Traumatised by typhoons and the earthquake, our children may spend many nights, worried by the nightmare in which the earth suddenly opens up her enormous mouth and swallow everything, as our son puts it in his slumber.
Ryota, Niigata, Japan
I am here for twenty years and have been part of the Hanshin earthquake. People here forget and move on with their lives. Here life line is gas, water, electricity. I went as a volunteer believing life line was life, compassion and sharing. Being thankful we are still alive and can help each other.
Thomas C Kantha, Osaka, Japan
It's funny. This afternoon at lunch I polled about 12 teachers at the elementary school where I work. My question was this: do you have a bag ready in case a bad earthquake hits closer (we've felt just about every one of the 200+ aftershocks, it seems) next time? And no-one said yes. They asked me if I have a bag ready, I said no but after this last batch of quakes I'm making one this week. Their reply: well, if the big one hits, we're coming to your house!
Gwen, Kiryu, Gunma, Japan
Your article on the earthquake in Niigata left me a sense of inaccuracy. The comment the country's worst earthquake in almost a decade cannot be totally wrong; however, as it will have been only ten years since the Great Hanshin Awaji earthquake which hit my town with more than 6,000 dead involved, it is simply my doubt if the said comment can be accurate. During the past 10 years, there have been many earthquakes in Japan, though not all of them had the disastrous impact as this one.
Nobue Kawano, Kobe, Japan
My sister is in Tokamachi, one of the worst hit areas. She has only been in Japan for four months (on a JET placement) she has been left in a total state of bewilderment. She's not been allowed back in her apartment block so is sleeping in a near by school with other JETs. She has been issued a ration card for water and food. Luckily she hasn't been hurt and we are able to keep in touch with her via her mobile phone.
Kaye Hopkins, Bridgnorth, Shropshire
With my Mother living in Fort Pierce, Florida where two monster hurricanes have recently made landfall destroying much of her town, and my daughter and son-in-law living in Odate, yet to be heard from after the latest earthquakes, I feel that natural disaster is the plague of the twenty-first century. Those writing from Japan, are there any indications yet of the conditions for those living north of Niigata?
Nancy, Edinburgh, Scotland
As someone who lived in Tokyo for nine years and returned to the UK last year, I really appreciate now the fact that I live in a brick house in a place that knows nothing about earthquakes! The feeling of vulnerability is horrible, and I feel for the people I still know living there. It's something that you can't appreciate unless you've lived in a place like that.
Bruce, Reading, UK
I have fond memories of Niigata and the people who live there. I visited Japan with in 1998 and lived with a family in Niigata for a week (they stayed with me in 1992). Although I have not been in touch with the family for a while, who live in an apartment block in the centre of Niigata, I am hopeful that they are unhurt. Niigata is a wonderful place and the people are extremely friendly and welcoming. I can't wait to go back some day. My thoughts go out to all those who are affected, especially the people of Niigata.
Darren, Sheffield, England
I'm from Japan but stay in England to study. When I lived in Tokyo before, I heard about the future big earthquakes in the Kanto-capital area. Government said that we could use the good facility for quakes repeatedly. However, I still can't stop feeling unease. There is still construction of skyscrapers in the waterfront area, despite suggestions of insecurity from some sources. I wish the government would be cautious for the definite measures for disaster.
Kyoko N, Birmingham (student)
I was watching TV when the first tremor came. There was a jolt that knocked things to the floor. We ran out into the street where neighbours were gathering. The ground continued to sway like a cross channel ferry on a rough day. My friend was in a public bath when the quake hit. Everyone rushed out with towels on. One old lady remained in the tub, saying "it'll be ok".
Niigata, Niigata city, Japan
Everyone living in Japan for an extended period has experienced many earthquakes. Most of these are forgotten fairly soon after they occur. However, the quake in Niigata is not one that I will forget. Here in Fukushima Prefecture (the neighbouring county to Niigata), we had to stop what we were doing several times in the evening. There were three very strong and long tremors which were followed by several smaller ones. However, I am not aware of any damage or injuries occurring in this area. The first tremor felt similar in intensity and length to another large earthquake that occurred recently in this area (its epicentre was near Sendai which is in the county north of us). However, we felt several more tremors during the earthquake in Niigata. It is amazing that there were not more casualties. A bullet train derailing at 210kph, tunnels collapsing, etc. could have caused many deaths, but fortunately the death toll appears to be a lot smaller than it could have been.
Mike Bradley, Fukushima Prefecture, Japan
In Ibaraki, just north of Tokyo, the two initial tremors had a magnitude of 4. Not enough to shake anything off shelves in our flat, but the length and number of aftershocks this time as well as the particular frequency of plate movements within the last couple of months is unnerving. Especially when you consider that the Tokyo area experiences a large earthquake every 60-80 years on average. The Great Kanto Earthquake in 1923 killed over 200,000.
Michael Green, Ibaraki, Japan
Unbelievable! 3 days after a major typhoon from which we are still recovering we are hit by a major earthquake! here in Toyama near the centre of the shake - the room shook pretty badly for a fair while - and this happened multiple times! - this week has made me aware of the power of the elements!
Jenny Elsby, Oyabe, Toyama, Japan
The world's effort should focus on the natural disasters, instead of making war. If the same earthquake happened in India, or Morocco, it may have killed thousands of people. I admire a lot the Japanese progress in earthquake detection, but much more work should be done. For me, I witnessed an earthquake in a visit to Beirut, although it was not very strong, I was conscious that not all countries in the world are ready for an earthquake. We should act to prevent disasters, everywhere in the world.
Woah, that was a nasty one. Up here in northern Saitama, the quakes were a Shindo 5- ! It was the most powerful quake I had ever experienced here in Japan. I heard it was no big deal in Tokyo, but up here it was a rocker. The house I was in felt like it was dancing around, things were falling all over the place!
Mark, Sugito, Saitama, Japan
So far all the comments (mine included) are from places other than from Niigata, where the earthquakes are centred. That probably gives you a good indication that life is not normal in anyway in Niigata at the moment! I only live on the second floor of my apartment building, but my mother-in-law, also in Tokyo, arrived home and was about to enter her front door of their 14th storey apartment when a major earthquake was felt. The shaking was so bad that she just had to brace herself against a wall outside the entrance as it was not possible to enter inside.
Dale, Tokyo, Japan
I was visiting friends in Ota city, just south of Tokyo, and we were just eating dinner. They live on the 6th floor of an apartment block, and the walls were moving! The TV started the 'Earthquake warning' right after the first shock hit. A bit late...Then the aftershocks were pretty powerful. It also turned out that the building had actually moved, their wooden flooring was jammed under the skirting boards! They think it was only about 4 where I was, so I can only imagine how bad it was at Niigata! I just hope the death toll doesn't rise...
This has been a dreadful summer for typhoons and earthquakes. The first one last night hit and seemed to last for ages. We knew straight away it had to have been a big one somewhere. The earthquakes carried on through the night, with another one around 11.30 pm. I think we had seven in all. We were supposed to be going for dinner on the 51st floor of a skyscraper - we decided discretion was the better part of valour and didn't go. We didn't fancy being that high during an earthquake. When you see the pictures of the shinkansen that jumped the tracks you realise what a miracle it was that no-one was hurt. It was on top of a bridge - if it had gone off that bridge the toll would have been a lot higher.
Clare Fremlin, Tokyo
Feeling your apartment and possessions shake so strongly is the most unnerving sensation. In the north of Niigata where I live, nothing was damaged, but we have been hearing horrible stories from friends in the south of the prefecture who have been badly hit. Many have spent the weekend in cars through another 200 or more aftershocks. All through this it has amazed me how calm and supportive my Japanese friends have been. In a country so prone to the elements, strong nerves seem to be part of this nation's character. We are all hoping that the large aftershock predicted this week will pass without more injury or damage to an already traumatised Niigata.
Si , Niigata, Japan
I live in Tokyo and yet another earthquake woke me up this (Monday) morning at 06.05. It just gets scarier every time. I hope this will be over soon.
Vanessa Åsell, Tokyo
I was staying on the border with Niigata prefecture and the wooden building I was staying shook quite violently. There was a series of strong aftershocks which carried on through the night.
Matt Malcomson, Tokyo, Japan
These were the strongest tremors I have experienced in ten years in Tokyo. Despite being more than 100 miles from the epicentre I had to steady my tall bookshelves which were swaying precariously. A few smaller items toppled over.
Chris, Tokyo, Japan
We spent Saturday evening repeatedly diving for cover under the kitchen table as glasses came crashing down from the shelves and pictures fell off the walls. At the time we were up in our weekend cottage in the mountains near Minakami, in northern Gunma prefecture, which is perhaps 80km from the worst-hit town in Niigata prefecture. This was the worst quake we had experienced in ten years or so of living in earthquake zones.
The unusual - and frightening - thing about this one was that the strong shocks kept on coming over such a long period. Within a couple of hours of the first tremor there were at least two more which were strong enough to shake objects off shelves, and there were smaller ones every few minutes for several hours. Our children ended up refusing to come out from under the table, and ate their supper under there, as every time they emerged, another quake sent them running back to cover. We were lucky that the only real damage we had was a dozen or so broken glasses, and there were a few minor landslips on the track leading up to our cottage. We packed up and headed back to Tokyo early as the aftershocks were continuing this morning, but we had to take a more roundabout route than usual as the closest sections of expressway were still closed due to earthquake damage.
Walker family, Tokyo, Japan
We're in Niigata, about 50 miles I guess from the epicentre. It was pretty scary as nothing like this has happened in Niigata for 40 years. The house rattled quite severely for about 30-45 seconds then everyone ran about packing bags "in case of a quick move", then went into the street to check on neighbours. Luckily, we're far enough away for there to have been no visible damage, although police cars, etc were heard all night. We felt the first tremor (about magnitude 6) at 17h54 local time (GMT-8?) and then about 10 or 11 more before we finally felt ok to go to bed at around 2am.
Nigel, Shirone City, Niigata Japan
I was sitting in the classroom when all of a sudden the room started shaking quite violently. It wasn't my first earthquake but it was the strongest one I have felt. Luckily, well for the Kanto region, it wasn't strong enough to destroy any buildings, but after the last two typhoons and now this, I wonder if it is the right time to be in Japan?
Rob Bright, Ofuna, Japan
I was watching "The Day After Tomorrow" on video with my girlfriend at the time of the quakes. We kept turning off the video after each shock and watching the reports on TV. After a while it became difficult to work out which was fiction and which was reality!
Mark, Tokyo, Japan
There is always a distinct point where you know it isn't just a trembler but something big. This was one of those times. I was in the bath at the time and the water was slapping against the sides.
Richard Tunaley, Tokyo, Japan
Yes, actually I just felt a couple more tremors here in the north west side of Tokyo. Actually, I was in the east north area of Tokyo when we felt the first tremor, there was one about 10 minutes ago, and another just a couple of minutes ago very small one. Pretty normal here to feel really small ones every once and a while. Actually, it has been reported and you should check local news like the Daily Yomiuri or the Japan Times that we have had 24 typhoons. That is a record breaker. Your agency said ten. That's totally wrong. You should correct that. Every year since I have lived here we have typhoons. It is part of life here.
Micheline, Tokyo, Japan
Micheline's comment about you incorrectly reporting the number of typhoons is incorrect. There have been 24 typhoons in the Pacific this year. However, all 24 did not hit Japan. Only 10 hit Japan (as you reported). 24 is an average number of typhoons. However, for 10 to hit Japan is just bad luck - they can go anywhere (or in many cases just fizzle out over the ocean).
James, Tokyo, Japan
We could tell from the first quake that it was some distance away by the length of the secondary wave; indeed it was so long we started to feel seasick. Three quakes over 6.0 in Niigata within about 30 minutes. Some areas have had 17 quakes over 4.0 and otherwise more than 80 smaller quakes in just a few hours. No damage in Tokyo. So far a few casualties reported from Niigata area, two having died from falling walls. But we remember from Kobe how the figures drastically increased after 24 hours. Many railway lines are stopped. We worry about remote villages in the mountains which have been well soaked by the last and severe typhoon, and no doubt there will have been many avalanches. Such villages are very vulnerable.
Bob Ridge, Tokyo, Japan
We didn't feel a thing over here. So I just want to say we are all okay in Nagoya and it's business as usual.
Scott Wallace, Nagoya, Japan
I am in Tokyo, and we felt at least three distinct tremors lasting for over a minute or more. After the typhoon last week one would hope that Mother Nature would deal us a kinder hand, but sadly not as the deaths, now confirmed as at least three, attest.