Ferocious wind and rain is lashing parts of eastern India and Bangladesh as Cyclone Amphan makes landfall.
Millions of people were evacuated in anticipation of the storm, which originated in the Bay of Bengal.
The storm, the first super cyclone to form in the area since 1999, is forecast to cause deadly storm surges, severe flooding and mudslides.
Covid-19 and social-distancing measures have made mass evacuations more difficult for authorities.
Cyclone Amphan began hitting the Sundarbans, a mangrove area around the India-Bangladesh border, on Wednesday afternoon and is forecast to move north and north-eastwards near the major city of Kolkata in India’s West Bengal state.
Amphan is expected to move further into Bangladesh on Thursday, and later Bhutan.
The storm was the first super cyclone in the Bay of Bengal since one in 1999 that killed thousands of people but its winds have since weakened slightly, according to BBC Weather.
The eye of the storm was forecast to be fully over land by 18:30 local time (13:00 GMT), with wind speeds of 150-160km/h (93-99mph) and gusts of up to 175km/h.
A Bangladesh Red Crescent volunteer helping villagers to evacuate became the first fatality after the boat he was in capsized in strong winds, the organisation said.