Kathmandu, Sep 10 - Twenty passengers died and dozens more are feared to have perished as an overcrowded bus plunged into a river in northern Nepal Thursday, in the worst road accident in the Himalayan republic this year.

Police in Sundhupalchowk district said the accident occurred in a village called Sukute while the bus was heading towards Kathmandu.

Carrying about 60 passengers, it veered off the road and fell almost 30m below into the swirling Sunkoshi river, fed with heavy rain in the past few days.

Though boats trawled the river for survivors, by evening only four people had been found alive with no signs of dozens of passengers.

Police said 20 bodies have been found. Most of the victims are yet to be identified.