Heavy rains have been lashing Tamil Nadu's Chennai as Cyclone Nivar hurtles toward India's southeastern coast.

Nivar is expected to cross the coasts of Tamil Nadu and Puducherry as a very severe cyclonic storm late on Wednesday, the Indian Meteorological Department (IMD) said.

"The cyclone is set to bring winds gusting up to 145 kilometers per hour."

Rain has already felled trees and flooded much of Chennai. Tens of thousands of people have been asked to leave homes and move to relief centers in southeastern states, reports BBC.

All fishing boats have been advised to return to harbors. 

The National Disaster Response Force of India has deployed 30 teams in Tamil Nadu, Puducherry, and Andhra Pradesh, and 20 more teams have been kept on standby to help assist local authorities on possible evacuations of residents from vulnerable coastal areas, reports the Hindustan Times.

As there are fears of flooding in Chennai, people living in low-lying areas are being evacuated.

In Tamil Nadu, the state government has declared a public holiday and advised people to stay indoors. Buses, trains, and flights have been suspended.

"People have been advised to stay indoors and those living in low-lying areas were asked to shift to safer places. We are providing food and drinking water to the people, and their Covid-19 tests will also be done," Pondicherry's Chief Minister Velu Narayansamy told ANI news agency.

Also, senior IMD officials told ANI that the cyclone is intensifying and could cause structural damage, uprooting trees and crops, and even destroying thatched and tin-roofed houses when it strikes.

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