At least 58 Rohingya Muslims are believed to have been on boats that capsized off western Myanmar trying to escape a cyclone.
It is believed one large boat with an engine was towing two smaller boats off the coast of Rakhine state when they hit rocks.
It is understood that about 100 people were on board up to five boats when they capsized.
Forty-two people apparently made it to shore but at least eight bodies have been found.
Brian Agland, CARE Australia's Myanmar country director, has told Radio Australia's aid agencies are preparing for the storm surge.
"In the case of this cyclone we've had a few days to prepare, which is unlike Cyclone Nagis," he said.
"We've been able to mobilise all of our staff, we have 32 staff based up in the area closest to the storm, right up along the Bangladesh border."
Fleeing the storm
The passengers were displaced Rohingya Muslims who have been mainly living in camps since violence flared between Buddhists and Muslims in the area last year.
They were apparently attempting to flee from the path of Cyclone Mahasen. The storm is expected to hit the coast later this week.
About 140,000 displaced people are living in camps in the region. At least 45,000 are in the direct path of the storm around the town of Sittwe.
Barbara Manzi, head of the Myanmar office of the UN Office for the Coordination of Humanitarian Affairs, reported the boats struck rocks off Pauktaw township after evacuations began on Monday.
The United Nations warned last week that the tropical cyclone could bring "life-threatening conditions" to thousands of people living in camps in the west of Myanmar.
"The possibility of the cyclone hitting has added a real urgency to our plans," said Vivian Tan, a spokeswoman for the UN refugee agency.
"We're building temporary shelters made out of bamboo which will hopefully stand the heavy rains, but with a cyclone, you just don't know what will hold up."
Nearly 20,000 Rohingyas are living in makeshift camps in Pauktaw after last year's violence.
This includes about 12,000 in flood-prone areas, according to UN data.
The mostly stateless Rohingya Muslims are denied citizenship by the Myanmar Government and considered by many in the country to be immigrants from Bangladesh.
The slow-moving Cyclone Mahasen has been raised to a category four warning level by Bangladesh authorities.
© ABC 2013
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