Boat carrying evacuees sinks off West Burma

Aid agencies said the boat, carrying up to some 200 passengers ahead of Cyclone Mahasen expected to hit the area later in the week, capsized off western Burma.

It sank off Pauktaw township in Rakhine state late on Monday, leaving an unknown number of people missing.

Tens of thousands of Rohingya Muslims are living in temporary camps in Rakhine after violence last year.

The UN had called for an urgent evacuation ahead of the storm, warning that many areas where displaced people are now living are in low-lying coastal areas at risk of flooding or tidal surges.

Barbara Manzi, head of the United Nations Office for the Coordination of Humanitarian Affairs (UNOCHA), told the BBC from Sittwe that search-and-rescue operations were ongoing.

"It appears that this boat left the camp with the blessing of the authorities before hitting rocks," she said.

There were between 100 and 200 people on board the boat, she added, with some survivors.

Burmese officials began evacuations this week, after warnings the cyclone may hit neighbouring Bangladesh from Thursday, bringing heavy rain and flooding to western Burma.

This could hit an estimated 140,000 displaced people - mostly Rohingya - who are living in makeshift shelters in Rakhine, aid groups say.

They have been displaced since violent clashes between Rakhine's Muslim and Buddhist communities in June and October 2012.