Rescue workers on the Samoan islands and Tonga are continuing to search for survivors after a tsunami struck, killing at least 149 people.
The prime minister of Samoa said 110 people were dead on his islands and the devastation "was complete".
Officials said planes carrying aid supplies were arriving on Samoa and nearby American Samoa.
They said tens of thousands of people need help in villages swamped by waves triggered by Tuesday's huge earthquake.
The United Nations said it was sending an emergency team to Samoa.
'No house standing'
"The devastation caused was complete," Samoan Prime Minister Tuilaepa Sailele told Radio New Zealand after inspecting the south-east coast of the main island of Upolu, the hardest-hit area.
"In some villages absolutely no house was standing. All that was achieved within 10 minutes by the very powerful tsunami."
He said his own village of Lesa had been washed away.
Samoan authorities have said that some islanders remain unaccounted for and may well have been washed out to sea or buried under tonnes of debris, says the BBC's Phil Mercer in the Samoan capital Apia.
But nearly two days after huge walls of water crashed into coastal areas the massive recovery effort is starting to take shape, he says.
In nearby American Samoa, a US territory, Governor Togiola Tulafono said at least 30 people had been killed. And in Tonga, officials said nine people were dead.
Amateur video footage showed villages destroyed, homes flattened and cars lodged in treetops.
Residents and tourists fled to higher ground as boats were swept inland and cars and people sucked out to sea.
US President Barack Obama declared a major disaster in American Samoa and pledged a "swift and aggressive" government response.
The European Union released an initial amount of 150,000 euros (£137,000; $220,000) in aid for the victims, and Australia and New Zealand also pledged assistance.
The Red Cross has set up camps for those who have lost their homes, the UN Office for the Coordination of Humanitarian Affairs said.
'River of mud'
The 8.3-magnitude quake struck at 1748 GMT on Tuesday, generating 15ft (4.5m) waves in some areas of the islands.
Returning New Zealand holidaymakers told of "truckloads" of bodies in the worst hit area on the southern side of Upolo, in Samoa.
"We've seen pick-up trucks carrying the dead... back to town," Fotu Becerra told radio Newstalk ZB, the AFP news agency reported.
Joey Cummings, a radio broadcaster in Pago Pago told the BBC that he watched from a balcony as a five-metre (15ft) wave struck and "the air was filled with screams".
He said a "river of mud" carried trees, cars, buses and boats past his building, which is practically at sea level.
The Pacific Tsunami Warning Centre (PTWC) said the quake struck at a depth of 33km (20 miles), some 190km (120 miles) from Apia.
Small tsunamis reached areas as far away as New Zealand, Hawaii and Japan.
An Indian Ocean tsunami on 26 December 2004 - which killed about 230,000 people in 11 countries - is the worst on record.
Separately on Wednesday a 7.9 magnitude earthquake struck a different fault line off the Indonesian island of Sumatra, killing hundreds of people.
It was followed a day later by another 6.8 magnitude quake in the same region.
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