Islamabad  - Eighteen people were killed when a passenger van plunged into a deep ravine in north-west Pakistan, media reports said Wednesday.

The bus carrying 18 passengers and the driver fell 100 metres off the mountain road in the Dankoo area in Buner district of North West Frontier Province on Tuesday night.

According to the Urdu-language Aaj TV news, the only survivor was an eight-year-old boy who suffered minor injuries.

Bad weather was the main cause of the accident, the report quoted police as saying.

Locals from nearby villages retrieved the bodies from the gorge and took them to Buner hospital. (dpa)