Two express trains were partially swept off a flooded bridge over a river in central India overnight, killing at least 20 people and injuring 100, the government said on Wednesday.

Divers using gas cutters pulled out passengers trapped in waterlogged coaches and 300 had been rescued by early morning, officials said. Dozens were rushed to hospital in critical condition.

"We are trying to rescue passengers. Relief work is going on on a war footing. We are checking all carriages to look for trapped passengers," said ministry spokesman Anil Saxena.

Twelve coaches of the Kamayani Express to Varanasi from Mumbai derailed near Harda in the central state of Madhya Pradesh just before midnight. Six coaches of the Janata Express derailed around the same time, the railway ministry said.

Heavy monsoon rains and the tail-end of a cyclone have killed more than 100 people across India in flooding, landslides and building collapses in recent days. – Reuters