With a rapt world watching the drama unfold live on television, the tsunami raced across the Pacific, forcing the evacuation of thousands of residents amid fears of a repeat of the carnage that caught Asia off guard in 2004.

This time, though, the wave surges barely exceeded 1m at their worst, and Pacific islands had ample time to prepare because the quake's epicentre was several thousand kilometres away.

By the time the tsunami hit Hawaii - a full 16 hours after the quake - officials had already spent the morning ringing emergency sirens, blaring warnings from aeroplanes and ordering residents to higher ground.

Picturesque beaches were desolate, million-dollar homes were evacuated, shops in Waikiki were shut down, and residents lined up at supermarkets to stock up on food, and at petrol stations.

In Japan last night, more than 24 hours after the quake, officials had ordered the evacuation of about 245,000 households along the country's Pacific coast. Images showed houses flooded in seawater in a section of Kesennuma, northern Japan.

One of the biggest waves, about 1.2m high, hit the northern island of Hokkaido. Some piers were flooded but there were no reports of major damage.

Japanese weather agency officials kept their alert up well into Sunday evening, saying further waves could be on their way.

It was the first warning for a major tsunami in 17 years and only the fourth since 1952, the Japan Meteorological Agency said.

"Carelessness could be the biggest enemy," Prime Minister Yukio Hatoyama said.

"In the past, even if the waves were not so big, there has been great damage with 2m-high tsunami."

In Samoa, residents headed for high ground as warnings of a possible tsunami brought back horror memories of the disaster that claimed 183 lives just five months ago.

About 4am, sirens, radio and television broadcasts, and text messages alerted the country to the threat to those in low-lying coastal areas.

Caroline Bilkey, the New Zealand High Commissioner, arrived in Samoa about 3am from New Zealand. By the time she got to her home, people were making their way on foot and by car away from the coast.

"It was good to see the whole country mobilise - people were calm and they took it seriously," said Ms Bilkey.

Thousands of people took to the hills on the main island of Upolu, and police said there were no reports of waves or sea surges hitting the country.

In Tonga, where hundreds of people fled inland hours ahead of the tsunami, the National Disaster Office received reports of a wave up to 2m high hitting a small northern island, deputy director Mali'u Takai said. There were no reports of damage.

In Fiji, Anthony Blake, the Disaster Management Office duty officer, said no unusual wave activity had been reported.

Mr Blake said coastal evacuations had taken place on Vanua Levu, Fiji's second biggest island, and in the Lau and Lomaiviti island groups. About a third of Fiji's 800,000 people live in those areas, he said.

In Tuvalu, one of the lowest lying islands, there were no major disturbances.

Sumeo Silu, co-ordinator of the National Disaster Committee, told the stuff.co.nz website: "We told the people as quickly as we could. We advised them to come to the widest part of the island, and to come to the double-floor building. The people have been very responsible."