A woman has suffered serious injuries after she was hit by a police car in south west England.
The accident happened last night on the outskirts of Bristol city centre.
Police said the car was at the time responding to a 999 call about a man allegedly making threats with a knife.
Avon and Somerset Constabulary said the woman was left with "possible life-threatening head injuries" as a result of the accident.
She is being treated in Southmead Hospital in Bristol.
A spokesperson for the police 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 Independent Police Complaints Commission and the local police professional standards department have been made aware of the incident.
Police also said a man had also been arrested on suspicion of assault and a knife has been seized.
Anyone able to help establish the circumstances of the crash is asked to contact the force's collision investigation unit by calling the 101 non-emergency number.Reuse content