Eleven people were killed and dozens of others injured when a train derailed after hitting a boulder that had fallen on to the track in southern India, officials said.

Railways Minister Suresh Prabu said the boulder fell from a nearby hill and derailed nine coaches and one food car.

At least 42 people were taken to hospital, including 17 in a serious condition, after the accident near Bangalore, the capital of southern Karnataka state, police officer Ranbir Sharma said.

Rescuers used gas cutters to open one badly crushed coach on the Bangalore-Ernakulam Intercity Express to remove passengers trapped inside, said Amar Nath, a bank executive who was on board.

"The train came to a screeching halt and I thought that it may have hit something," said Mr Nath, who was unhurt.

Accidents are common on India's vast rail network, which carries 23 million people every day. They are often attributed to human and equipment errors.