Search on for 50 missing after Bangladesh sinking

Coastguards, the navy and fishermen have rescued about 60 people since the boat went down on Wednesday morning 15 kilometres (nine miles) off the southern district of Cox's Bazaar.

"So far about 60 passengers, about half the number of passengers of the boat, have been rescued," Bangladesh Border Guard commander Lieutenant Colonel Zahid Hasan told AFP.

He said the border guards have held 25 survivors, both Bangladeshis and Rohingya, for questioning and there were about 35 others who were picked up by fishing boats.

"We have not found any dead bodies yet," he said.

Security officers have asked coastal villages to report other survivors, Hasan said.

"A navy ship is continuing its patrol in search of any bodies," Faizul Kabir, a local coastguard commander in the Teknaf area.

The latest tragedy comes after a boat carrying some 135 passengers, mostly Muslim Rohingya refugees who had fled unrest in neighbouring Myanmar, sank in the Bay of Bengal on October 28. Only around half a dozen made it to safety.

Hundreds of thousands of Muslim Rohingya have fled Myanmar in past decades to escape persecution, often heading to neighbouring Bangladesh, and recent outbreaks of violence, in June and October, have triggered another exodus.

Survivors of Wednesday's sinking said the overloaded wooden motorboat had a capacity of 70 passengers and it capsized after a passenger fell into the sea and the boat turned abruptly in a bid to rescue him.

Since the unrest erupted in Myanmar, Bangladesh has been turning away boatloads of fleeing Rohingya.

The policy has been criticised by the United Nations but Bangladesh said it was already burdened with an estimated 300,000 of the minority group.

Myanmar's 800,000 stateless Rohingya, described by the UN as among the world's most persecuted minorities, are seen by the government and many Burmese as illegal immigrants from Bangladesh.