New Delhi - At least 28 people have died in four days of torrential rains in India's southern Tamil Nadu state, news reports said Wednesday.

Most of the deaths occurred due to wall collapses, electrocution and drowning in the seven coastal districts since Sunday, PTI and IANS news agencies reported.

The heavy rains and strong winds were being caused by a depression over the Bay of Bengal between the Tamil Nadu and Sri Lanka coasts, PTI reported.

The local weather office predicted heavy showers over the next 24 hours.

Tamil Nadu capital Chennai was also affected. Schools and colleges shut down as most streets remained waterlogged.

At least 20 domestic and international flights were delayed since Tuesday due to flooding on the airport runway.

Lakes, canals and dams were flowing at or above danger levels, officials said. People were being evacuated from lowlying areas in all seven coastal districts and relocated to temporary relief camps.

Large areas of paddy crop had also been inundated.

Fishermen were warned not to go out to sea. (dpa)