Dhaka,  At least 15 people were killed as cyclone Sitrang slammed the Bangladesh coasts and weakened to a tropical depression in the early hours of Tuesday.

With high winds and heavy rains, the cyclone erased houses, crops and infrastructure in a vast swath of the country while most of the casualties were caused by falling trees, reports Xinhua news agency.

At least four people died in southern Bhola district where fallen trees blocked roads and electricity supply was not to be fully restored, local sources said.

A man, his wife and their infant daughter were killed when a tree fell on their house in eastern Cumilla district on Monday, a local official said on Tuesday.

The remaining eight fatalities were reported from other parts of the country, including capital Dhaka.

The coasts have been battered by ferocious winds, which uprooted trees and homes, ripped roofs off buildings and caused widespread power and water outages.

Scores of villages in parts of the country have reportedly been flooded and many susceptible houses have been damaged fully or partially.

Due to heavy rainfall, hundreds of thousands of people have been evacuated or sought safe shelter before the storm hit the country's coast from the Bay of Bengal on Monday.

The danger signal No. 7 has been sounded for most parts of Bangladesh and major ports while fishing boats, trawlers and maritime vessels over the north bay have been advised to remain in shelter till further notice.

Television footage showed widespread devastation in coastal areas of Bhola, Khulna, Chittagong and other districts.