Indian police say at least 21 children were killed when their school bus skidded off a mountain road and plunged into a gorge in the foothills of the Himalayas.

Police officer Sunil Kumar says initial reports indicate the bus driver was speeding and lost control at the edge of the gorge, dropping some 200 feet (60 meters) to the ground below.

The accident occurred on Monday in the Kangra Valley, about 500 kilometers (300 miles) from New Delhi.

Kumar says a rescue operation is continuing after nightfall. Few other details are available.