A powerful 7.8-magnitude earthquake hit Indonesia's Sumatra island early today, triggering a tsunami alert in nearby Thailand.
The quake struck at a depth of 46km off the northwest coast of Sumatra at 5:15am (6.15am Malaysian time), according to the US Geological Survey, but there were no reports of damage.
Indonesian geologists said it had a magnitude of 7.2 and the epicentre was 60km southeast of Sinabang, on Simeulue Island of Aceh province, which was devastated by a massive quake and tsunami in 2004.
The Pacific Tsunami Warning Center issued a watch for tsunamis in Sumatra but said a destructive ocean surge was not expected.
The National Disaster Warning Centre in Thailand said there was a high risk of a tsunami on the Andaman Coast, which was battered by the Indian Ocean tsunami in 2004 that killed an estimated 5,400 people in Thailand alone.
Officials in Sinabang and the Indonesian capital of Jakarta said there were no immediate reports of damage.
Electricity was down in the Acehnese capital of Banda Aceh but mobile phones were working.
"Our personnel haven't found any damage in Sinabang," local police chief Dedi Junaidi told MetroTV.
Residents of Banda Aceh said they felt the earth shaking powerfully for about a minute and many fled their homes or piled onto motorcycles to head inland in fear of a destructive tsunami.
"People panicked and ran out of the house, it lasted almost a minute," an AFP reporter in Banda Aceh said.
"I saw a lot of people who live close to the sea using motorcycles to drive inland."
Indonesia sits on the Pacific "Ring of Fire," where the meeting of continental plates causes high volcanic and seismic activity.
The meeting point of the Indo-Australian plate and the Eurasian plate off the western coast of Sumatra causes frequent earthquakes and scientists believe it is only a matter of time before a major catastrophe strikes the area again.
Indonesia was the nation hardest hit by the 2004 tsunami, with at least 168,000 people killed when the sea surged over the northern tip of Sumatra after a 9.3-magnitude quake split the seabed to the island's west.
A 7.6-magnitude quake killed about 1,000 people in the port of Padang, western Sumatra, in September last year.
courtesy of Malaysiakini