JAKARTA—A massive earthquake and strong aftershock rattled Indonesia's westernmost province of Aceh on Wednesday, spurring fears of a tsunami in the same region where a 2004 tsunami killed more than 200,000.

The 8.6-magnitude earthquake was felt as far away as Thailand, Malaysia and India. The Pacific Tsunami Warning Center had issued a tsunami watch Wednesday afternoon in Asia but later canceled it, saying that while a significant tsunami was generated by the quake, the threat for most areas had diminished.

The initial alert said the tsunami watch was in effect from Indonesia to India, Sri Lanka, Australia, Somalia, Oman, Iran, Bangladesh, Kenya, South Africa and Singapore.

 

Indonesian President Susilo Bambang Yudhoyono said that early reports were that there was limited damage. "There is no tsunami threat," he said Wednesday evening ahead of a news conference with British Prime Minister David Cameron. "The tsunami early-warning system is working well and at the moment there are no casualties."

India also canceled its tsunami warnings and alerts for several states and territories, including the Andaman and Nicobar Islands in the Indian Ocean.

In a statement, India's Home Ministry said it had asked the chief secretaries of the Andaman and Nicobar Islands, and all east-coast states, to advise fishermen not to venture out to sea and to take other precautions.

Teams from the National Disaster Response Force were placed on standby in case they were needed to carry out emergency relief efforts, the agency said.

The U.S. Geological Survey said the powerful quake was centered about 20 miles beneath the ocean floor, about 300 miles from Aceh's provincial capital.

Indonesian television news showed crowded roads as people tried to drive away from the coast.

"It felt like the earthquake back when we had a tsunami in 2004," said driver and Aceh resident Edi, who like many Indonesians goes by one name. "Everybody ran around in a panic and we ran up a hill."

People in Banda Aceh screamed "God is great!" as they jumped into cars and onto the backs of motorcycles, clogging streets as they fled to high ground, according to the Associated Press.

Coastal residents in Sri Lanka were told to move to higher ground. Thailand's National Disaster Warning Center issued an evacuation order to residents in six provinces along the country's west coast, including the popular tourist destinations of Phuket, Krabi and Phang-Nga. Thailand later canceled its tsunami warning.

Indonesia sits atop a web of fault lines that makes the sprawling archipelago prone to volcanic and seismic activity. A giant 9.1-magnitude quake off the country on Dec. 26, 2004, triggered a tsunami in the Indian Ocean that killed 230,000 people, nearly three quarter of them in Aceh.

Indonesia's government has improved its monitoring of earthquake data since then by positioning buoys to take sea-level readings and warn of potential tsunamis. Officials have noted the problem of getting timely information to people who live in remote areas of coastal Sumatra.

Experts said the kind of devastation seen in the 2004 disaster and last year in Japan was caused by a particular type of earthquake. During Wednesday's quake, the tectonic plates were likely shifting sideways rather than up and down, leaving less of a chance for the giant waves, said Susanne Sergeant, a seismologist at the British Geological Survey.

"The earthquake today was different from that in 2004 off Aceh and in Japan," last year, and less likely to create massive water displacement, she said.

India issued a tsunami warning for Andaman and Nicobar Islands and the eastern coast on Wednesday after a 8.7 magnitude quake in Indonesia shook major cities, causing panic and sending people fleeing onto the streets.

The Indian National Centre for Ocean Information Service issued a red
high-level warning for the islands, and also put out lower alerts for the coasts of Andhra Pradesh and Tamil Nadu.

India's tsunami warning center said waves measuring up to 6 metres were expected along parts of its eastern coast, which was heavily hit by the 2004 tsunami. Smaller waves were expected to hit the remote Andaman and Nicobar islands.

The US Geological Survey said 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.

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

A massive earthquake off the coast of Sumatra has triggered a tsumani alert around the Indian Ocean.

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 the quake was centered 33km beneath the ocean floor around 495km 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.

US monitors issued an Indian Ocean-wide tsunami watch but said it was not yet certain a giant wave had been generated.

"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 Centre said.

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 quarters of them in Aceh.