At least 20 people were killed Saturday when an overloaded bus skidded off the slippery road and rolled into a gorge in the northern Indian state of Himachal Pradesh, said police.

The accident took place when a private bus was coming to Chamba town when it fell into the gorge near Rajera, some 10 km from the Himalayan town of Chamba, about 475 km from the state capital Shimla.

The mountainous area where the accident took place experienced some heavy rains over the past few days.

The toll could rise as the exact number of passengers in the bus was not known.

The accident took place three days after over 30 people were killed in a similar bus accident in the northeast Indian state of Meghalaya on Wednesday.

Overloading of passengers and goods is blamed for the frequent bus accidents in India.