Indonesia has lifted a tsunami warning issued after a powerful earthquake off Sumatra sent islanders rushing to high ground.

Sumatra, Indonesia. Image by Fabio Achilli / CC BY 2.0.

Sumatra, Indonesia. Image by Fabio Achilli / CC BY 2.0

The US Geological Survey (USGS) said the earthquake had a magnitude of 7.8. It was centred under the sea at a depth of 15 miles.

Shallow earthquakes are more likely to cause damage, but the USGS said the quake was located far from land, about 409 miles from the town of Muara Siberut.

Disaster Mitigation Agency spokesman Sutopo Purwo Nugroho said no damage or casualties were reported so far, but panicked people in several cities and villages on Sumatra island and in the Mentawai island chain fled to higher elevations.

Sumatran elephants

Sumatran elephants were not affected by the quake threat. Image by Vincent Poulissen / CC BY-SA 2.0

Indonesia, the world’s largest archipelago, is prone to seismic upheaval because of its location on the Pacific “Ring Of Fire,” an arc of volcanoes and fault lines circling the Pacific Basin.

A massive magnitude-9.1 quake off Indonesia in 2004 triggered a tsunami that killed 230,000 people in a dozen countries. Most of the deaths were in Indonesia’s Aceh province on Sumatra.

Marjina, a resident of Sikakap in the Mentawai islands, about 430 miles from the epicentre, said the quake was felt only weakly there, but the tsunami warning caused panic among villagers.

(Press Association)