Police are appealing for witnesses to come forward after a girl was hit and run over by a dirt bike in Sydney’s far south-west yesterday.

Emergency services were called to a park on Copperfield Drive in Rosemeadow after reports a nine-year-old girl had been hit by a dirt bike at 5.45pm.

Officers believe a person rode an unregistered dirt bike across a sporting field before riding down a hill, striking the girl and running over her head and chest.

The person rode away from the scene, and witnesses rushed to the aid of the girl. 

She was treated for facial injuries by paramedics at the scene and was taken to Westmead Children’s Hospital in a serious condition.

An investigation is under way.

Anyone who witnessed the incident or with any information is urged to contact Crime Stoppers.