A mass evacuation saved thousands of lives when India's strongest cyclone in 14 years struck, but aid workers warned on Sunday (October 13) that around a million would still need help after their homes and livelihoods were destroyed.

Cyclone Phailin was expected to dissipate within 36 hours, losing momentum as it headed inland after making landfall on Saturday from the Bay of Bengal, bringing winds of more than 200 kph (125 mph) that ripped apart homes and tore down trees.

Authorities in the eastern state of Odisha said the death toll stood at seven people, all killed as the storm slammed in from the ocean. Six died under falling trees and one when the walls of her mud house collapsed.

The relatively low number of casualties stands in contrast to the 10,000 killed by Odisha's last big cyclone in 1999.

The building of hundreds of cyclone shelters since then, along with early warnings which started five days before the storm's arrival and orderly - often forceful - mass evacuations helped minimise loss of lives, aid officials said.

At least 873,000 people in Odisha and adjacent Andhra Pradesh spent the night in shelters. Others sought safety in schools or temples, in what officials called one of India's largest evacuations.