Villagers walk around debris and a house that was smashed by a tsunami in Pago Pago Harbor after an earthquake on the island of American Samoa, September 30, 2009.
When the tsunami warning came to the Samoa archipelago, it was a matter of minutes before death struck. Church bells rang. Men banged on gas cylinders. School buses took children inland.
But the disaster still left at least 110 people dead.
The Pacific islands were so close to the epicentre of the earthquake that a wall of water hit Samoa within eight minutes after the Tsunami Warning Center in Hawaii sent its first bulletin Tuesday.
Several Samoans said they heard no sirens or warnings, but fled as soon as they were woken up by the earthquake.
Nevertheless, the fact that scores left for safety underlined that lessons from the 2004 Indian Ocean tsunamis have not been forgotten.
"The reaction of the population and the authorities was better than expected," said Peter Koltermann, head of the Tsunami Unit at UNESCO's Intergovernmental Oceanographic Commission.
Boosting tsunami detection was a major priority after the Indian Ocean disaster, which killed 230,000 people. But in Samoa's case, geography didn't leave much chance.
The earthquake occurred about 200 kilometres from Samoa. It took the first wave less than half an hour to cover the distance, not a surprising pace since tsunamis can move as fast as jetliners.
The magnitude 8.0 underwater earthquake struck at 6:48 a.m., local time. The first bulletin from Hawaii came out at 7:04 a.m. The tsunami hit American Samoa at 7:12 and the Samoa at 7:32 a.m.
There were heart-wrenching stories - such as the mother who saw the wave sweep her two toddlers from her arms - but also signs that people acted quickly.
"Our fire services gave out a warning about 10 minutes after the initial earthquake. The church bells started ringing in the villages," Olga Keil, a reporter in Samoa, told the BBC, "and the good thing is that we've had tsunami drills in the past so we basically knew exactly where to go."
The morning tremor rattled American Samoa for a minute, triggering an exodus toward higher ground, the local newspaper reported from Tutuila, the territory's main island. It described how school buses took children inland and residents in sheltered areas opened their yards and driveways to the displaced.
"There were police cars going up the road just telling residents to go up to higher ground in a very orderly fashion," tourism official David Vaeafe told Sky News. "In the mountains, young men were banging gas cylinders as church bells, like they were calling people to church."
"There were victims in Samoa partly because of the close geographical distance or possibly because the local alert system was insufficient, didn't work properly or did not have the time," said Badaoui Rouhban, director of UNESCO's disaster reduction section.
The Pacific Tsunami Warning Center in Hawaii has operated since 1965.
However, a warning system also depends on a lower-tech chain of communication that needs to be reliable, Dr. Koltermann said.
When the displaced Samoans returned in the afternoon, they were confronted by power outages, buildings smashed like matchboxes, cars and buses tossed about and flipped over, muddy streets strewn with palm leaves, tree branches and sheets of corrugated metal, as well as ships wrecked along the docks.
The 2004 Indian Ocean tsunamis took an hour to hit Thailand and two hours to reach India and Sri Lanka, but still killed tens of thousands of people who were taken by surprise. In the wake of that disaster, an early-warning tsunami detection networks was set up for Indian Ocean countries.
With a report from Agence France-Presse
Tu Thanh Ha