The bodies of India's defence chief and 12 others who died in a helicopter crash will be brought to New Delhi on Thursday, where the top general will be laid to rest with full military honours, Defence Minister Rajnath Singh said.

General Bipin Rawat, his wife and 12 defence personnel were en route to a military staff college in southern India when the air force helicopter they were travelling in came down near the town of Coonoor on Wednesday.

Only one of the 14 on board survived the crash. The cause of the crash is being investigated.

Rawat, 63, was appointed as India's first chief of defence staff by Prime Minister Narendra Modi's government in late 2019. The position was set up with the aim of integrating the army, navy and air force.

In a brief statement in parliament, Defence Minister Singh said the Mi-17 V5 helicopter took off at 11.48 a.m. on Wednesday from the Sulur Air Base. The base lost contact with the aircraft seven minutes before it was scheduled to land at a hillside military area at 12.15 p.m.

"Locals spotted a fire in the forest near Coonoor and rushed to the spot where they observed the wreckage of military helicopter engulfed in flames," Singh said.

Rawat, who served in the army for over four decades, would be laid to rest with full military honours, Singh said.

The lone survivor of the crash, an air force group captain, is on life support at a military hospital.

"All efforts are being made to save his life," Singh said.