The number of deaths from bushfires that have already claimed 170 lives in the Australian state of Victoria is likely to rise, officials have warned.
Police believe some of the fires were started deliberately - actions which Prime Minister Kevin Rudd said amounted to "mass murder".
Survivors have recounted how they fled walls of flames. Some people died in their cars trying to escape the fires.
Some rural towns have been completely destroyed.
Police have sealed off a number of sites, including the devastated small town of Maryville, as possible crime scenes.
Victoria State Premier John Brumby said: "We have had whole communities just completely wiped out, completely obliterated, by what people would describe as literally a fireball that just came over the hills and devoured everything before them.
"It's the largest natural disaster in our state's history and Australia's history."
Scorching temperatures, drought, tinder-dry bush and constantly-changing wind directions on Saturday helped fan the blazes, affecting an area of some 3,000 sq km (1,200 sq miles).
Temperatures dropped and conditions improved on Monday to help the tens of thousands of firefighters, backed by soldiers, bring the fires under control.
But there were around 30 fires still burning in Victoria with several communities at risk, officials said. More than 700 homes have been destroyed.
16 February 1983: 75 dead, 2,300 homes destroyed in "Ash Wednesday" bushfires in Victoria and South Australia
8 January 1969: At least 22 dead, 230 homes lost in rural Victoria
7 February 1967: 62 dead, 1,300 homes destroyed in fires in Hobart, Tasmania
13 January 1939: 71 dead, 700 homes destroyed in "Black Friday" fires in Victoria
February - March 1922: 60 die in Gippsland, eastern Victoria
Two other states - New South Wales and South Australia - have also been hit by blazes, but the fires there are said to be largely contained or burning away from residential areas.
Forecasters warn temperatures could rise again later.
Shocking stories are emerging from survivors in the worst-hit areas.
The BBC's Nick Bryant, at a relief centre in the hamlet of Whittlesea near the devastated town of Kinglake, said people thought they had hours when in fact they only had minutes to escape the fast advancing flames.
Some described escaping down roads lined with burning trees, while their cars caught fire in the furnace-like heat.
One man said he siphoned off the water from his vehicle's radiator to try to save the life of a neighbour who had been set alight.
Kinglake resident Thomas Legrary described finding a neighbour with up to 50% burns on his body. They put him in the swimming pool to keep him cool.
Elsewhere in Kinglake, Jack Barber and his wife fled just ahead of the flames but found their escape route blocked by fallen power lines and trees.
NICK BRYANT'S AUSTRALIA
One man said he hardly had time to react let alone move, so fast were the advancing walls of flames.
They took shelter at a school, but that also caught fire. They then ran to an exposed cricket ground ringed by trees where they found five other people.
"All around us were 100ft (30m) flames ringing the oval and we ran where the wind wasn't. It was swirling all over the place. For three hours, we dodged the wind," Mr Barber said.
Hospitals have been dealing with a number of badly-burned people.
"[Here] it has been very busy. We've been treating firemen with burns, and sadly getting lots of dead on arrivals," Karen Farthing, a nurse at a Victoria hospital, told the BBC News website.
A former Melbourne newsreader, Brian Naylor, and his wife were among those killed on Saturday when the flames took hold in the Kinglake district.
Search for friends
Many residents of fire-ravaged towns are now involved in a desperate search for friends and relatives missing since the flames tore through the tiny communities.
The bodies of people have already been found trapped in the burnt-out wreckage of cars and homes, and investigators fear more will be found when a full search of the charred settlements can be carried out.
HOW BUSHFIRES SPREAD
1 Fires start in hot dry windy weather 2 Embers blown ahead of fire front 3 Spot fires start where embers land
He admitted that the advice to residents - to evacuate early or stay and defend their homes - had on this occasion not worked.
Australia's head of state, Queen Elizabeth II, has spoken of her "shock and sadness" at the number of deaths, and has praised the extraordinary work of the emergency crews at the scene.
The British and New Zealand governments have both offered to help deal with the fires.
The Australian Red Cross, which has about 400 volunteers working in Victoria, has launched an appeal for donations.
Relatives concerned about family members in the affected areas can contact the Australian Red Cross 24-hour helpline on (0061) 393283716 or, from the UK, the British Red Cross international tracing and message service on 0845 053 2004.
Bush fires are common in Australia, but the current blazes have eclipsed the death toll from what had been the previous worst fire in 1983, when 75 people died on a day that became known as Ash Wednesday.
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