The islands are a few miles from the Myanmar border, and camps set up in Cox's Bazar had provided refuge for about 200,000 Rohingyas Muslims from Myanmar.
Shamsul Alam, a Rohingya community leader, told Reuters that damage in different camps was severe with almost all the 10,000 thatched huts in the Balukhali and Kutupalong camps destroyed.
"Most of the temporary houses in the camps have been flattened," Alam said.
Omar Farukh, a community leader in Kutapalong camp, said conditions were dire: "Now we're in the open air." But weather officials said the cyclone was not as bad as they had feared. "The severity was less than the apprehension," Shamsuddin Ahmed, a weather official based in Chittagong said.
Officials in Chittagong reported winds gusting up to 135 kph (85 mph), and said low-lying coastal areas were flooded by a storm surge with waves 2 metres (7 feet) high.
The cyclone was expected to weaken in Bangladesh by late morning as it moved inland towards India where authorities have warned of heavy rain in the northeastern states of Tripura, Mizoram, Manipur, Nagaland and Arunachal Pradesh.
In the eastern Indian state of Bihar, 24 people have been killed in recent days, either by lightning or in collapsed dwellings.
(Writing by Simon Cameron-Moore; Editing by Robert Birsel)
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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