At least 36 people have been killed after an overcrowded bus plunged into a gorge in the northern Indian state of Uttarakhand on Monday.

The bus was travelling from Garhwal in the Himalayas and was headed to the town of Ramnagar, carrying around 60 people, despite only being able to accommodate 42 passengers.

More than 20 have been injured, said Deepak Rawat, a senior state government official.

"So far, 36 casualties have been confirmed," Mr Rawat said.

Footage from the scene 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.

India's Prime Minister Narendra Modi offered his "deepest condolences to those who have lost their loved ones in the unfortunate road accident".

Mr Modi's office said the families of those killed would receive 200,000 rupees ($3,605) in support, while those injured would receive 50,000 rupees ($901).

Uttarakhand Chief Minister Pushkar Singh Dhami said he had ordered an investigation into the accident.

Reuters/AFP