Dozens of people are missing and some feared dead after their boat capsized while fleeing a cyclone in western Myanmar.

More than 100 Rohingya Muslims were tossed into the stormy sea when the boat ferrying them out of danger tipped over. Eight bodies have been found and more than 50 people were missing and feared dead.

The boat, which was carrying refugees as part of a mass evacuation before Cyclone Mahasen is expected to make landfall, sank after it struck rocks off Pauktaw township in Rakhine state, said Barbara Manzi, head of the Myanmar office of the UN Office for the Coordination of Humanitarian Affairs.

Nearly 70,000 Rohingya people who sought refuge in camps in western Myanmar after outbreaks of religious violence needed to be relocated to higher ground, said the UN’s humanitarian coordinator in Myanmar, Ashok Nigam.

“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,” she said.