A violent tropical storm has killed at least 116 people and devastated an estimated 100,000 homes in impoverished rural areas of eastern India and Bangladesh.

Winds of up to 120 kilometres an hour tore across north-eastern India and neighbouring Bangladesh overnight Tuesday (local time), ravaging mud and tin-roofed homes, uprooting trees and bringing down electricity lines.

Officials in the states of West Bengal, Bihar and Assam said a total of 114 people had been killed. Two others were reported dead in Bangladesh, including a police officer.

“The storm has left a trail of destruction everywhere,” West Bengal minister of state for civil defence Srikumar Mukherjee told local television from the disaster scene in North Dinajpur district.

The number of people killed and houses damaged could rise further, disaster officials said, as relief was rushed to the isolated areas, where roads were blocked by fallen trees and phone lines were down.

The storm was an extreme form of what is locally known as a “nor’wester” – a weather pattern that develops over the Bay of Bengal during the hot months of the year, the West Bengal weather office said.

Nor’westers normally bring refreshing winds that blow across the low-lying region in March and April and lower temperatures, Gokul Chandra Debnath, the office’s director, said.

Mohammad Ibrahim, a 40-year-old resident of Hematabad village in West Bengal, said by phone it was the worst storm he had ever seen.

“God has saved me, but taken away my home and everything,” he said, adding that he been injured by a falling tree.

Survivor Abhijit Karmokar told local television that many people had been injured or killed by flying objects, particularly tin sheeting used as roofing on many of the flimsy homes that succumbed to the storm.

“Some of these tin roofs just sliced through people… It was total darkness… We stood no chance,” he said.

‘Casualties will rise’

Homeless people were being shifted to local schools and government offices.

In Bihar, the worst-affected state, chief minister Nitish Kumar returned from an aerial tour of the disaster area to say damage was more extensive than initially thought.

Seventy-two people had died and an estimated 40,000 homes were destroyed in Purnia, Araria and Kishanganj districts, the state disaster management office said.

Families of the deceased have been offered compensation of 150,000 rupees ($3,600).

At least 50,000 homes were destroyed and 38 people died in West Bengal, four people perished and 500 homes were lost in the northern state of Assam, and 12,000 homes were damaged in Bangladesh, officials said.

“Unconfirmed reports reaching here suggest that the number of casualties will go up,” an official in the Bihar Disaster Management Department, Vayas Mishra, said.

In Bangladesh, northern Rangpur was the worst hit. District administrator BM Enamul Haq said two people had died, including a police officer crushed under a collapsed wall.

The storm demolished a police barracks, leaving dozens injured, two of whom remain in critical condition.

“We haven’t yet learnt the full extent of the damage. We know the storm has damaged at least 12,000 homes. It has also flattened crops on a huge tract of land in the Rangpur division,” Mr Haq said.

The cyclone came amid unseasonably high temperatures across much of northern India, where the mercury is already above 40 degrees Celsius in many areas.