Kathmandu  - At least six people were killed and dozens more injured in a bus-tractor accident in eastern Nepal, police said Thursday.

Police said the bus crashed into a tractor in Sunsari district, about 400 kilometres east of the Nepalese capital, late Wednesday night.

Among those killed where the people travelling on the tractor. More than 30 people were injured and some were in serious condition.

The cause of the accident was not immediately known. However, police suspected speeding by the bus was the main cause of the accident.

Hundreds of people are killed each year in road accidents blamed mostly on careless driving and overcrowding on public transport, made worse by narrow and dangerous mountainous roads. (dpa)