The quake, with a magnitude of 8.8, has killed at least 122 people in mainland Chile and prompted the evacuation of coastal areas on Easter Island – famous for its monumental stone statues – as well as Samoa and American Samoa.
Countries across the Asia-Pacific region are readying emergency measures drawn up after the Indian Ocean quake of 2004, with the tsunami expected to hit in the next 24 hours.
Michelle Bachelet, the outgoing Chilean president, declared a "state of catastrophe" in central Chile and said a huge tidal wave had swept into the Juan Fernandez Islands. Local radio stations reported serious damage on the archipelago, which reputedly inspired the novel Robinson Crusoe.
The president-elect, Sebastian Pinera, said more than 122 people had died in the quake, and the toll was rising quickly. Bachelet said there were more than 85 deaths just in the Maule region, at the quake's epicentre.
"We have had a huge earthquake with some aftershocks. We're doing everything we can with all the forces we have. Any information we will share immediately. Without a doubt, with an earthquake of this magnitude, there will be more deaths," Bachelet said.
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