Indonesia has issued a tsunami warning after a quake with a preliminary magnitude of 8.9 hit waters off westernmost Aceh province.
The US Geological Survey said on Wednesday the quake was centred 33 kilometres beneath the ocean floor around 495 kilometres from the provincial capital of Banda Aceh.
Said, an official at Indonesia's Meteorology and Geophysics Agency who goes by only one name, said a tsunami warning has been issued. Indonesia straddles a series of fault lines that makes the vast island nation prone to volcanic and seismic activity.
A giant 9.1-magnitude quake off the country on December 26, 2004, triggered a tsunami in the Indian Ocean that killed 230,000 people, nearly three quarter of them in Aceh.
"Earthquakes of this size have the potential to generate a widespread destructive tsunami that can affect coastlines across the entire Indian Ocean basin," the US Pacific Tsunami Warning Center said.