KATHMANDU - Some passengers were riding on the bus's roof, according to police At least 35 pilgrims have been killed in a bus crash in Nepal, police say.

The crowded bus swerved off a road and plunged into an irrigation canal near the town of Parasi, 150km (93 miles) south-west of Kathmandu, officers said.

The bus was taking the pilgrims - mostly from the Indian state of Uttar Pradesh - to the Hindu pilgrimage site of Triveni, close to the Indian border.

Buses are often overcrowded in Nepal and accidents on poorly maintained mountain roads are common.

A police official, Gyan Bikram Shah, told Associated Press that the driver had lost control on roads that were slippery because of rainfall.

He said the bus was so crowded that people were riding on the roof.

Another police officer, Deepak Raya, told AFP from the crash site that, according to survivors, there were about 75 people on board the bus. Rescuers have recovered 35 bodies.

He said the bus became fully submerged after veering off the road.

Officials said water levels in the canal were elevated as a result of monsoon rains. Rescuers have drained water from it to search for survivors, police officer Ram Dutta Joshi told the Reuters news agency.

Last October, at least 41 people were killed when a bus swerved off a mountain road and plummeted 400m (1,300ft) into a river in eastern Nepal.