Floods have killed at least 100 people and displaced hundreds of thousands across much of India with the southern state of Kerala worst hit, authorities said Saturday.

With rains predicted to worsen in coming days, the government ordered military teams to form rescue units and airlift food to stranded villages across Kerala.

At least 48 people have died since Thursday in floods in Kerala, where the beaches and hill resorts are a major international tourist magnet, state police spokesman Pramod Kumar told AFP.

In neighboring Karnataka, at least 24 people have been killed with nine people missing. The western states of Maharashtra and Gujarat have also been badly hit by annual monsoon storms.

Media reports said at least 27 people have lost their lives in Maharashtra, with several major roads closed by floods. Storm accidents killed eight people in the key Gujarat cities of Ahmedabad and Nadiad.

The worst fears are for Kerala where the police spokesman said about 120,000 people have moved into emergency relief camps.

"There are around 80 places where flood and rains have triggered mudslides, which we cannot reach," Kumar added.

"About 200 people are stranded at one place. We are trying to use air force helicopters to drop food to them."

Kerala's main airport at Kochi has been closed since Friday. About 500 people died in floods in the state last year which were the worst in nearly a century.

More than 600 relief camps in Karnataka are now filled with 161,000 people, a state disaster management authority official told AFP.

"The rains have eased in the region and we think the water will soon start to recede. There are parts of northern Karnataka, coastal regions and the Western Ghats which are badly hit," the official added.

While the monsoon rains are crucial to replenishing water supplies, they kill hundreds of people every year.