Jebun Nahar, a government official, said 14 people died, mostly after they were hit by falling trees, and two died after a boat sank in squally weather in the Jamuna river in the north. “We still have not got all the reports of damages,” she said.

People evacuated from low-lying regions such as remote islands and river banks were moved to thousands of multistorey cyclone shelters, said Disaster Management Ministry secretary Kamrul Ahsan. “They spent the night in cyclone shelters.”

Cyclones – the equivalent of hurricanes in the North Atlantic or typhoons in the Northwest Pacific – are a regular and deadly menace on the coast of the northern Indian Ocean where tens of millions of people live.

Most worrying for authorities was the predicted storm surge of up to three metres (10 feet) above normal tide levels, which could inundate areas home to millions of people.

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Cyclone Sitrang lashes Bangladesh, leaving 16 people dead

Cyclone Sitrang lashes Bangladesh, leaving 16 people dead

The newly formed silt island of Bhashan Char, where Bangladesh has been relocating Rohingya refugees to alleviate overcrowding in their refugee camps, was expected to be hit by heavy rains and strong winds.

“The Bhashan Char shelters are protected by a 19-feet-high embankment. Still, we asked people to stay at home,” a senior security officer said from the island.

The government had hoped to evacuate about 2.5 million other people ahead of the storm, the country’s disaster management minister Enamur Rahman told reporters earlier on Monday.

“The evacuation has already begun from the morning,” the minister said, adding that more than 7,000 shelters have been readied in an effort to keep casualties to a minimum.

At least 250,000 people had already been evacuated from coastal districts to cyclone shelters by the afternoon, two regional administrators said.

Tens of thousands of volunteers were mobilised for the effort, said a spokesman for the local chapter of the Bangladesh Red Crescent Society.

“We have already evacuated the most vulnerable people, especially those who live in remote islands and river banks and those who live in flimsy houses,” said Aminul Ahsan, regional administrator of Barisal.

“In some places we have used force to bring people to cyclone shelters. It is for their own safety,” another regional administrator said.

The Red Crescent Society has mobilised tens of thousands of volunteers to help villagers evacuate, spokesman Shahinur Rahman said.

In the neighbouring eastern Indian state of West Bengal, several thousand people were also being evacuated as a precaution, with more than 100 relief centres opened, officials said.

“A special squad is making a round-the-clock vigil along the coastline of the state,” West Bengal government minister Arup Biswas said.

“Fishermen have been asked not to venture into the sea. Ferry services have also been suspended,” he said.

Last year, more than a million people were evacuated along India’s east coast before Cyclone Yaas battered the area with winds gusting up to 155km/h (96mph)– equivalent to a Category 2 hurricane.

The 1970 Bhola cyclone, one of the world’s worst natural disasters, killed several hundred thousand people in Bangladesh – then known as East Pakistan – and India.

In recent years, better forecasting and more effective evacuation planning have dramatically reduced the death toll from such storms.