Car debris flies into crowd at demolition derby

Spectators at a demolition derby in Utah got more than they bargained for on Saturday evening when a stray driveshaft flew more than 30 rows into the packed crowd.

Two women and a teenage boy were taken to hospital after the incident, which occurred after a truck was hit and rolled onto its side.  As the vehicle righted itself, the metre-long steel part flew into the crowd and hit a number of fans.

Footage from multiple angles of the incident shows the crowd's horrified reaction as well as the speed with which the shaft hurtled through the air.

A spokesperson for the Heber Valley Medical Center said the teenage boy had been released from hospital late on Saturday evening while a third victim had been transferred to another hospital.

Witnesses said those injured had been struck on the ankles, arms and neck.