A tsunami crashed into Chile's coast yesterday in a potential portent of disaster across the vast Pacific ocean as nations went on alert for towering waves generated by a killer earthquake.
Sirens blared in French Polynesia to warn residents to find higher ground as a tsunami watch went into effect across the Pacific's 'Ring of Fire' after the 8.8-magnitude quake in Chile, which left at least 147 people dead.
Nations along an arc stretching from New Zealand to Japan implemented emergency plans that were beefed up after the Indian Ocean disaster of 2004, when a series of immensely destructive tsunamis killed more than 220,000.
The Pacific Tsunami Warning Centre, set up by Pacific governments after a tsunami unleashed by a deadly 9.5 magnitude earthquake in Chile in 1960, warned of possible "widespread damage" as outsized waves raced across the ocean.
"We could be looking at an all-day event," US National Weather Service meteorologist Eric Lau told AFP in Washington.
"It will stop once it hits the land masses on the other side of the Pacific, in Asia. The wave is spread out across the entire body of water in the Pacific."
Authorities in the US state of Hawaii, where the warning centre is based, said residents would shortly start hearing tsunami sirens.
"If you live anywhere in the evacuation zone, you have to evacuate," Oahu Emergency Management Department John Cummings said. "We're going to treat this as a destructive-type tsunami."
One tsunami measuring 2.34 metres slammed into Talcahuano, one of about 11 coastal towns in Chile hit by the wave, according to the Pacific centre. There was no immediate word of casualties.
Chile's remote Robinson Crusoe Island, some 700 km from the mainland, was also smashed by a huge wave, while President Michelle Bachelet announced a partial evacuation of Easter Island.
The pan-Pacific tsunami warning applied also to Central America, and authorities as far afield as Russia's Sakhalin island were monitoring the potential for tidal trouble.
In the tourist paradise of French Polynesia, the local government said the first waves were expected to reach the Gambier archipelago imminently. Sirens and loudspeaker announcements woke up residents in the middle of the night.
New Zealand warned of a wall of water up to three metres high potentially hitting some of its outlying islands and part of the South Island, as the country's National Crisis Management Centre went on alert.