At least 106 people died in the fiercest cyclone to hit Bangladesh and eastern India since 1999, officials said Friday as aerial footage revealed immense flooding in coastal areas.

Amphan, only the second "super cyclone" ever recorded over the Bay of Bengal, bulldozed houses, tore off roofs, uprooted trees and left millions without power when it hit late on Wednesday.

Mamata Banerjee, premier of West Bengal said Friday that 80 people died in the Indian state, while Bangladesh's toll rose to 26, health department spokesperson Ayesha Akhter said.

The total was much lower than the many thousands of fatalities recorded in previous cyclones, thanks to better forecasting and the timely evacuation of over three million people.

However, huge damage was done in coastal areas as vast volumes of seawater rushed inland, inundating villages and shrimp farms that are vital to the Bangladeshi economy.

The United Nations in Geneva said Friday that the saltwater is expected to have "a severe impact on livelihoods for the next 2-3 years".

West Bengal's capital Kolkata was also badly hit, with 19 dead, parts of the old city flooded and hangar roofs at the airport caved in on top of aircraft. The bodies of 11 people who were electrocuted were recovered from the flooded streets.