At least seven people were killed and millions were left without power as Severe Cyclone 'Remal' lashed the coasts of Bangladesh with devastating winds of up to 120 kph and storm surges, inundating hundreds of villages.

'Remal' weakened into a cyclonic storm on Monday morning, sustaining wind speeds of 80-90 kilometres per hour, following landfall around midnight of Sunday, the Met Department said.

The department said that the weather system, which lay 150 km northeast of Sagar Island at 5.30 am, brought torrential rain and moved northeastwards to weaken further into a cyclonic storm.

Remal is the first cyclone in the Bay of Bengal ahead of this year's monsoon season, which runs from June to September. The cyclone was named Remal (meaning sand in Arabic) by Oman, according to a system of naming cyclones in the Indian Ocean region.

The cyclone has been accompanied by gusty winds and heavy rains, impacting areas including Barisal, Bhola, Patuakhali, Satkhira, and Chattogram.

In Patuakhali, one person was washed away by a storm surge while returning home to bring his sister and aunt to a shelter.

Another person died in Satkhira after falling as he ran for cover during the storm.

Five people were killed in Barishal, Bhola and Chattogram, Dhaka-based Somoy TV reported.

In Mongla, a trawler sank, leaving two people, including a child, missing.

The rural power authority has cut off electricity to 15 million people in coastal areas to minimise the damage from 'Remal', BD News reported.

The power outages have lasted over 12 hours in some areas, but electricity workers are preparing to restore the connections once the storm subsides.

Biswanath Sikder, chief engineer (planning and operation) of the Bangladesh Rural Electrification Board, said the storm was still ongoing as of 9:45 am in the coastal areas.

He estimated that a total of about 15 million people in the affected areas were without power.

According to the Met Office, Cyclone Remal has moved northward, crossing the coast and is currently positioned near Koira in Khulna.

The cyclone is expected to continue its northward trajectory, bringing increased rainfall and weakening to a lower intensity within the next 2-3 hours, the Met Department of Bangladesh said in a special bulletin at 3:30 am on Monday.

'Remal' sustained wind speeds of 80-90 kilometres per hour, following landfall around midnight of Sunday, the Indian Met Department said.

Heavy to very heavy rainfall with wind gusts on Monday morning braced most of Bangladesh under the influence of the storm.

Despite accurate forecasts and increased public awareness, weak embankments failed to withstand the cyclone’s force, inundating many villages.

Coastal areas experienced waves as high as 5 to 6 feet, exacerbating the destruction, according to the Met Office.

The storm on Sunday forced authorities to close the country's three seaports and the airport in the second-largest city Chattogram, BSS News reported.

Maritime ports of Payra and Mongla have been advised to keep hoisted great danger signal no 10.

As the cyclone progresses, the sea and coastal environments are predicted to gradually calm, although heavy rains and gusty winds persist in Dhaka and its surrounding areas.

Fishing boats and trawlers operating in the North Bay of Bengal and the deep sea have been advised to remain in a safe harbour until further notice.

Payra and Mongla ports have been instructed to hoist danger signal number 10, indicating severe conditions.

The Meteorological Department has warned that due to the cyclone's intensity and the air pressure difference, coastal districts and their remote islands and chars could face wind-driven tides 8-12 feet above normal.

Cyclone-prone Bangladesh designed most schools in coastal regions as cyclone shelters alongside dedicating structures to enable people to take refuge during surges and many of these multi-storey facilities have space for sheltering cattle as well.

Officials said on the low-lying Bhashan Char island, which is home to 36,000 Rohingya refugees from Myanmar, 57 cyclone centres were readied.

On Sunday, Bangladesh evacuated nearly 800,000 people from vulnerable areas.

Bangladesh's junior minister for disaster management and relief, Mohibur Rahman, said volunteers have been deployed to move the evacuees to up to 9,000 cyclone shelters. The government also closed all schools in the region until further notice.

Bangladesh shut down the airport in the southeastern city of Chattogram and cancelled all domestic flights to and from Cox's Bazar.

Bangladesh also suspended loading and unloading in the country's largest main seaport in Chittagong and moved more than a dozen ships from jetties to the deep sea as a precaution.

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