Seventy people, including children, have been hurt after a pile-up involving four passenger buses in Hong Kong.

Most injuries were minor.

The crash, which also involved a lorry, happened near a tunnel entrance in Tseung Kwan O Road in Lam Tim, a residential area in Kowloon.

Nine people suffered more serious injuries, police said.

What caused the smash was unclear.

Numerous firefighters, paramedics and police were called to the scene.

Several people lay on stretchers and at least one passenger was seen being helped from a vehicle.

A window on the side of a bus was shattered.

Some of the injured, including elderly people, were treated by paramedics at the scene.

A group of primary school pupils was seen sitting on the road and some of them had hand injuries.