A bus in India plunged into a deep Himalayan ravine on Monday, killing at least 36 passengers and injuring several others, a government official said.

Photographs released by government rescue teams showed the crumpled wreckage of the bus in thick undergrowth, with the twisted front of the vehicle squashed nearly flat.

Road accidents are common along the many mountainous roads in the Himalayan region, caused mostly by poor maintenance and reckless driving in the tortuous terrain.

“So far, 36 casualties have been confirmed,” Deepak Rawat, a senior official from the northern state of Uttarakhand told reporters.

“Three critically injured have been sent to hospital using a helicopter.”

A human chain of volunteers lined the steep slopes, and across a rushing river, helping pull out the wounded from the remains of the bus.

Dead bodies were carried out and laid on the back of a truck.

Prime Minister Narendra Modi offered his “deepest condolences to those who have lost their loved ones in the unfortunate road accident”.

Modi’s office said in a statement that the families of those killed would receive 200,000 Indian rupees ($2,380) in support, while those injured would get INR 50,000 ($595).

Uttarakhand Chief Minister Pushkar Singh Dhami said he had ordered an investigation into the accident, which took place in forested hills near the town of Almora.

Hundreds of people die in road accidents in India every year.