By Rajendra Jadhav

At least 18 people have died in the western Indian state of Maharashtra after torrential monsoon rains caused landslides and flooding that submerged low lying areas and cut off hundreds of villages, authorities said on Friday.

Rivers in Maharashtra were flooded after authorities released water from dams made full after many parts on the west coast received more than 200 mm (8 inches) of rain in 24 hours and some parts received as high as 594 mm rainfall.

At least four people died after a building collapsed in the financial capital Mumbai, and another 14 were killed in four landslides in other parts of Maharashtra, state government officials said.

"Rescue operations are going on at various places in Satara, Raigad and Ratnagiri. Due to heavy rainfall and flooded rivers, we are struggling to move rescue machinery quickly," said a state government official, who declined to be named.

Several dozen people were feared to have been trapped at landslides in Satara and Raigad districts, the official said.

In coastal districts, the Indian navy and army have been helping in rescue operation, Maharashtra chief minister Uddhav Thackeray said.

Thousands of trucks were stuck on a national highway linking Mumbai with the southern technology hub of Bengaluru, with the road submerged in some places, another Maharashtra government official said.

Hundreds of villages and dozens of towns in the affected areas of Maharashtra were without electricity and drinking water, he said.

In neighbouring southern states of Karnataka and Telangana some rivers are overflowing, and authorities are monitoring the situation, government officials said.

Seasonal monsoon rains from June to September cause deaths and mass displacement across South Asia every year but they also deliver more than 70% of India's rainfall and are crucial for farmers.