Helmet saves motorcyclist's life after he is hit by a flying rock

A video has emerged from China of a motorcyclist being hit in the head by a flying rock.

The dash cam video, filmed in Hechi, Guangxi Zhuang Autonomous Region on August 1, shows a three-kilogram stone shooting up from the road when a lorry runs it over and hitting the passing motorcyclist in the side of the head.

The rider is knocked unconscious and crashes by the side of the road.

According to doctors, he would have been killed had it not been for his helmet.