A powerful magnitude 8.6 earthquake and strong aftershocks struck off Indonesia yesterday, sending people as far away as southern India scurrying from buildings and raising fears of a disastrous tsunami like in 2004.
Indonesian President Susilo Bambang Yudhoyono said there were no immediate reports of casualties or damage in Aceh, the province closest to the initial earthquake. However, an aftershock of almost the same magnitude, less deep that the first quake, hit soon after he finished speaking.
The first quake struck at 3:38pm and an 8.2 magnitude aftershock just over two hours later, at 5:43pm local time. Two more strong aftershocks hit later.
The Pacific Tsunami Warning Center issued fresh tsunami warnings for the entire Indian Ocean after the aftershocks.
Only small tsunami waves of around 1m were reported to have hit the western coast of Sumatra.
However, authorities in India’s Andaman and Nicobar islands, to the north of where the quakes struck, said waves of up to 3.9m could hit there.
Individual countries, including Thailand, Indonesia, Sri Lanka and India, issued their own tsunami warnings and people near the coast in six Thai provinces were ordered to move to higher ground. Those alerts were later lifted.
The quakes were about 500km southwest of the city of Banda Aceh, on the northern tip of Sumatra, the US Geological survey said. The first was at a depth of 33km.
Indonesia’s disaster management agency said power was down in Aceh Province and people were gathering on high ground as sirens warned of the danger.
“The electricity is down, there are traffic jams to access higher ground. Sirens and Koran recitals from mosques are everywhere,” said Sutopo, spokesman for the agency.
Yudhoyono, speaking after the first quake, said there were no signs of a disaster.
“There is no tsunami threat although we are on alert,” he said at a joint news conference in Jakarta with visiting British Prime Minister David Cameron, who said Britain was standing ready to help if needed.
“The situation in Aceh is under control, there’s a little bit of panic, but people can go to higher ground,” Yudhoyono said.
Warning sirens rang out across the Thai island of Phuket, a tourist hotspot that was one of the worst hit areas in the 2004 tsunami.
“Guests from expensive hotels overlooking Phuket’s beaches were evacuated to the hills behind and local people were driving away in cars and on motorcycles. Everyone seemed quite calm, the warning had been issued well in advance,” freelance journalist Apichai Thonoy said by telephone.
Indonesian television showed people gathering in mosques in Banda Aceh. Many others were on the streets, holding crying children.
Yudhoyono said he had ordered a disaster relief team to fly to Aceh, which was devastated by the magnitude 9.1 2004 quake and tsunami.
In all, the 2004 tsunami killed about 230,000 people in 13 Indian Ocean countries.
Yesterday’s quakes were felt as far away as Bangkok, southern India and the Sri Lankan capital of Colombo.
The quakes were in roughly in the same area as the 2004 quake, which was at a depth of 30km along a fault line running under the Indian Ocean, off western Indonesia and up into the Bay of Bengal.
One expert told the BBC at least the first quake yesterday was a “strike-slip” fault, meaning a more horizontal shift of the ground under the sea as opposed to a sudden vertical shift, with less risk of a large displacement of water triggering a tsunami.