SHIMLA: At least 25 passengers were killed and 35 injured Thursday after their vehicle fell in a gorge in a mountainous region of India's northern Himachal Pradesh state, officials said.

The private bus was filled with more than 60 people, some of them sitting on the roof, when it plunged into a 150-metre (500-foot) deep gorge in Kullu district of the Himalayan state.

Kullu police chief Shalini Agnihotri told AFP that authorities launched a rescue operation immediatly and moved the injured to hospitals.

She said the toll could rise further.

Local media showed the mangled remains of the bus near a stream at the bottom of the gorge as locals made human chains to help survivors cross it.

The Himalayan state is prone to deadly accidents owing to its rugged terrain, with speeding and over-crowding adding to the safety hazards.

At least 15 people were killed in April after their bus fell into a gorge in a nearby district.

In India an average of 150,000 people die in road accidents each year. —AFP