Tropical Storm Nilam weakened Thursday after slamming into southern India, bringing heavy rain and a storm surge and displacing 150,000 people. At least six deaths have been reported in India and Sri Lanka.

Just before the storm made landfall Wednesday, an oil tanker with 37 crew ran aground off Chennai. One of its lifeboats capsized in the choppy waters, and one crew member drowned, the Press Trust of India news agency reported.

On Thursday, two helicopters searched in the Bay of Bengal for four missing crew members, said coast guard officer Gurdip Singh, adding that 32 were rescued from the tanker.

The cyclone had maximum winds of 45 mph after landfall but had weakened to a tropical depression. A storm surge of up to 5 feet had been forecast to flood low-lying coastal areas, the India Meteorological Department said. Fishermen were asked to stay at shore.

Power supply was disrupted to parts of Chennai, the capital of Tamil Nadu state, PTI said.

Arun Sankar K / AP

Ambulances stand on shore as people look at Indian ship Pratibha Cauvery that ran aground with people on board, reportedly due to strong winds on the Bay of Bengal coast in Chennai, India.

There were conflicting reports on the number of those killed.

“We are in the process of making a full assessment of the damage,” M. Jayaraman, a spokesman for the government, told The New York Times. “But we know that eight people have died and a total of 8,556 people from coastal districts in Tamil Nadu were affected due to Nilam. There are also been damage to roads and many trees have been uprooted.”

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State authorities turned 282 schools into relief centers in Chennai and the city's port halted cargo operations. Twenty-three ships were moved to safer areas.

About 150,000 people were moved to shelters in Nellore, district official B. Sridhar said.

In Sri Lanka, 4,627 people were displaced by flooding and 56 fled because of a landslide threat in the island's central region. One woman died Tuesday after a tree branch fell on her while another person was killed in flooding, the nation's Disaster Management Center said. Floods also damaged about 1,000 houses, it said.

Nilam is the third cyclone to hit India’s southern coast in recent years.

The Associated Press contributed to this report.

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