Ninetree Hill
A woman is in critical condition after being struck by a police car in Ninetree Hill, BristolGoogle Maps

A woman is in a Bristol hospital with 'life-threatening' injuries after being struck by a police car responding to a 999 call after receiving reports of a man armed with a knife. The police car was said to be on an emergency blue light run when the incident occurred.

A spokesman for Avon and Somerset constabulary said: "The police vehicle was on an emergency blue light run responding to reports of a man with a knife making threats in the Stokes Croft area.

"At about 10pm the police vehicle was involved in a collision with the woman at the junction of Gloucester Road and Ninetree Hill. The woman, who suffered possible life-threatening head injuries, has been taken to Southmead hospital."

The spokesman said the Independent Police Complains Commission (IPCC) had been informed, as had the force's own Professional Standards department. A man is also in custody after being arrested on suspicion of assault. A knife had also been seized. The identity of the critically-injured woman has not yet been released.

Police tape
There were 30 fatalities involving police cars responding to 999 calls in 2012/13Reuters

"The road has been closed to allow a detailed examination to take place," said the police spokesman. "We are keen to hear from anyone who may have been in the area at the time who may have information to help our investigation."

Anyone with relevant information is being asked to call the force's collision investigations unit on 101.

In August 28-year-old dad-of-two Aston McLean was killed when he was struck by a police car in Reading. In March 46-year-old James Sutton of St Leonards died after being struck by a police car in Hastings.

All accidents which involve police vehicles and result in death or injury are referred to the IPCC to investigate.

According to the most recent IPCC figures there were 30 fatalities involving police cars responding to 999 calls in 2012/13.