Earthquake hits off Indonesian coast

A 7.7-magnitude earthquake has hit off the coast of Sumatra in western Indonesia, triggering a brief tsunami warning, monitoring agencies said Monday. There are no reports of damage or casualties.

The U.S. Geological Survey said the quake struck about 240 kilometres from Bengkulu, Sumatra, just after 10:40 a.m. ET. The quake occurred at a depth of about 20 kilometres, the agency said in a statement.

The agency had initially estimated the quake at magnitude 7.5.

A local tsunami watch was briefly in effect for Indonesia, but "a destructive widespread tsunami threat does not exist based on historical earthquake and tsunami data," the Pacific Tsunami Warning Center said. The tsunami watch was subsequently cancelled.

The earthquake was reportedly felt in five towns in Bengkulu and West Sumatra provinces, said Tatok Yatimantoro of Indonesia's Meteorology and Geophysics Agency.

Aftershocks hit the area, with one registered at magnitude 5.0 about an hour after the first tremor.

'Everyone was running'

"Everyone was running out of their houses," said Sofyan Alawi, a resident of the city of Padang. She said loudspeakers in mosques had broadcast tsunami warnings and roads to nearby hills were soon swarming with cars and motorcycles.

"We kept looking back to see if a wave was coming," said resident Ade Syahputra.

The world's largest archipelago, Indonesia is prone to earthquakes and volcanic activity because of its location on the so-called Pacific Ring of Fire.

More than 1,000 people died after quakes struck off the coast of Sumatra in September 2009.