http://news.bbc.co.uk/2/hi/asia-pacific/4388579.stm The Indian Ocean is on tsunami alert after a quake off the coast of Sumatra, the Indonesian island that bore the brunt of the 26 December disaster. It struck just before midnight local time, with an estimated magnitude of 8.2, and caused widespread panic. There were unconfirmed reports of casualties from the tremor as people left coastal areas of Sumatra. Malaysia, Sri Lanka, Thailand and India are also on alert after forecasts of a "widely destructive tsunami". The quake struck between the Sumatran cities of Padang and Medan at around 2315 local time (1615 GMT) and lasted up to three minutes, according to Indonesia's Meteorological and Geophysics Office. Its epicentre was located at about 200km (125 miles) off the Sumatran mainland. Most people were in bed at the time and there were no immediate reports of damage, says the BBC's Tim Johnstone in the Indonesian capital, Jakarta. Reports from Banda Aceh say thousands came out into the streets, fearful of collapsing houses, while an official quoted by Reuters news agency spoke of "dozens" killed on the island of Nias. Communications were swamped, although some mobile phone messages were getting through. 'I heard my neighbours screaming' The 26 December tsunami caused major damage and killed tens of thousands of people in states across the region. Russ Evans, a seismologist from the British Geological Survey, told the BBC that Monday's tremor quake was almost certainly an after-shock of the earlier quake, which had a magnitude of 9. A new tsunami was certainly possible, he said, but on a smaller scale. The quake was felt across the region with people in the Malaysian capital, Kuala Lumpur, some 500km away, evacuating high-rise buildings and running out into the streets. "I was getting ready for bed, and suddenly, the room started shaking," said Kuala Lumpur resident Jessie Chong. "I thought I was hallucinating at first, but then I heard my neighbours screaming and running out." Thailand and India, badly hit by the 26 December disaster, issued tsunami alerts while Sri Lanka evacuated coastal areas.