KATHMANDU - AT LEAST 22 people were killed and 57 injured when an overcrowded bus carrying school children back from a picnic skidded off a highway in southern Nepal, police said on Friday.

'The bus was speeding and overturned, then fell 15 metres off the road,' said Mr Kal Bahadur Gurung, a local police officer from Nawalparasi, 100 kilometres west of Kathmandu.

The bus was carrying around 80 children, and most were around nine or 10 years old, the police officer said.

'Fifteen children died on the spot late on Thursday and the rest died undergoing treatment or on the way to hospital,' said Mr Gurung. -- AFP