A huge 7.6 magnitude earthquake struck off the Andaman Islands in the Indian Ocean on Tuesday, triggering panic as people fled their homes amid initial warnings of a possible tsunami.
A tsunami alert issued for India, Myanmar, Indonesia, Thailand and Bangladesh was later cancelled by the Pacific Tsunami Warning Center of the US National Weather Service.
"Sea level readings indicate that a significant tsunami was not generated," the centre said.
The police control centre in Port Blair, the main town of India's Andaman Islands, said there were no immediate reports of any major damage or casualties.
The quake hit at 1:55 am (1955 GMT Monday) around 263 kilometres (163 miles) north of Port Blair, and was around 33 kilometres (20.2 miles) deep.
The Andamans were badly hit by the 2004 Asian tsunami which was triggered by an earthquake off the Indonesian island of Sumatra and sent giant waves crashing into countries around the Indian Ocean.
"It was very frightening. Everything started shaking and people were running out of their homes," said Mrinal Sarkar, a villager in Diglipur in the northern Andamans.
"People are afraid to go back inside," Sarkar told AFP.
Mild tremors from the quake were felt 1,190 kilometres away in the eastern Indian port city of Chennai.
India's national tsunami warning centre said it had detected no sign of any abnormal surge in sea levels.
"We haven't issued any tsunami warning so far," said Ravichandra Vedula, an official with the Indian National Centre for Ocean Information Services in the southern city of Hyderabad.
"We are monitoring all data on water levels and no anomaly has been observed. Everything is normal," Vedula told AFP.
The epicentre was also around 364 kilometres southwest of the Irriwaddy Delta region of Myanmar which was devastated by a huge cyclone in May last year that left more than 138,000 people dead.
Thailand's National Disaster Warning Centre, which was set up after the 2004 tsunami, said it was monitoring events.
"We have been warned about the quake and are watching the situation. We have not yet issued an alert, we are still watching developments," an official at the centre said.
The 2004 tsunami killed more than 220,000 people, most of them in the northern Indonesian province of Aceh. Thousands of people were also killed in Sri Lanka, Myanmar, Thailand and India.
The Andaman and Nicobar Islands are some of India' most eastern pieces of territory. More than 350,000 people live in the territory flanked by the Andaman Sea and the Bay of Bengal, and it comprises some 572 islands.
The Andaman Sea area witnesses frequent earthquakes caused by the meeting of the Indian plate with the Burmese microplate along an area known as the Andaman trench.