New Delhi. Two passenger trains derailed in India on Friday, killing at least 50 people and trapping hundreds of others inside more than a dozen damaged coaches, officials said.

About 400 people were taken to hospitals after the accident, which happened in eastern India, about 220 kilometers (137 miles) southwest of Kolkata, officials said. The cause was under investigation.

Dattatraya Bhausaheb Shinde, the top administrator in the Balasore district, said at least 50 people were dead.

Nearly 500 police officers and rescue workers with 75 ambulances and buses responded to the accident, said Pradeep Jena, the top bureaucrat of the Odisha state.

Rescuers were attempting to free 200 people feared trapped in the wreckage, said D.B. Shinde, administrator of the state's Balasore district.

Amitabh Sharma, a railroad ministry spokesperson, said 10 to 12 coaches of one train derailed, and debris from some of the mangled coaches fell onto a nearby track. It was hit by another passenger train coming from the opposite direction.

Up to three coaches of the second train also derailed.

The Press Trust of India news agency said the derailed Coromandel Express was traveling from Howrah in West Bengal state to Chennai, the capital of southern Tamil Nadu state.

Indian Prime Minister Narendra Modi said he was distressed by the accident.

“In this hour of grief, my thoughts are with the bereaved families. May the injured recover soon,” tweeted Modi, who said he had spoken to the railway minister and that “all possible assistance” was being offered.

Despite government efforts to improve rail safety, several hundred accidents occur every year on India’s railways, the largest train network under one management in the world.

In August 1995, two trains collided near New Delhi, killing 358 people in the worst train accident in India’s history.

Most train accidents are blamed on human error or outdated signaling equipment.

More than 12 million people ride 14,000 trains across India every day, traveling on 64,000 kilometers (40,000 miles) of track.