Tsunami warnings have been lifted after two major underwater earthquakes struck in the Indian ocean off the coast of Indonesia.
The watch was partially lifted by the Pacific Tsunami Warning Centre (PTWC) after the quakes did not appear to have caused major damage.
Seismologists from the US Geological Survey (USGS) said the first earthquake hit near Aceh province on the island of Sumatra and registered a magnitude of at least 8.6.
An aftershock reported after the first quake measured 8.3, and prompted fresh tsunami alerts across the region.
IN PICTURES: Indonesia Reacts To Tsunami Warning
The initial earthquake was located 33km under the sea, the USGS said. Its epicentre was about 495km from Banda Aceh, the captial of Aceh province.
PTWC said a small tsunami had been generated by the quake, but that its strength was not enough to cause large-scale damage.
Indonesian President Susilo Bambang Yudhoyono said the country would "remain vigilant".
"Our warning system is working well," he said. "I have ordered the national relief team to fly immediately to Aceh to ensure the situation is under control."
The BBC said that in Jakarta buildings shook for up to five minutes during the quake.
The tremors were said to have been felt as far afield as the eastern Indian coast and Thailand.
People in Aceh province and the east coast of India rushed to higher ground after the alerts were issued.
View Indonesia Earthquake in a larger map
Prime Minister David Cameron is currently in Indonesia on a tour of Asia.
At a press conference where he announced a deal to sell Airbus aircraft to Indonesia, Cameron said that Britain would be ready to help the country "at this time of worry":
Indonesia is located on the so-called 'ring of fire', a deadly region of major seismic activity and one of the most active faultlines.
In 2004 an earthquake off the coast of Sumatra resulted in a tsunami which killed around 230,000 people on the coast of the Indian ocean.
That quake was one of the longest ever recorded and was reported to be between magnitude 9.1 and 9.3.