India and Bangladesh began a massive clean-up Thursday after the fiercest cyclone since 1999 killed at least 95 people, leaving a trail of destruction in its wake.

Cyclone Amphan flattened houses, uprooted trees, blew off roofs and toppled electricity pylons, while a storm surge inundated coastal villages and wrecked shrimp farms vital to the local economy.

Improved weather forecasting meant Bangladesh was able to move some 2.4 million people into shelters or out of the storm's direct path, while India evacuated some 650,000.

Bangladesh's Sundarbans forest chief Moyeen Uddin Khan told AFP the storm surge that smashed into the vast mangrove area -- which bore the brunt of the storm -- was "not as high as was feared earlier".

The area most affected by Amphan, the first "super cyclone" to form over the Bay of Bengal since 1999, was the Satkhira district of southwest Bangladesh.