A suspected burglar rammed a silver Ford Fiesta into a police car before speeding away from the scene.
Police have launched an appeal to find two men suspected of being in the car that crashed into the patrol car in St Chads Road, Tilbury, at about 1.30am on Wednesday, December 17.
The female office in the car was hospitalised for a check-up but did not require treatment.
The Fiesta was later found abandoned nearby.
Police searched the area for the suspects, who are also suspected of being involved in burglaries in Tilbury.
Anyone with information about the users of the Fiesta, index number W634YHJ, which had been sold by a previous owner a few weeks earlier, should contact officers at Chigwell Road policing office on 101 or call Crimestoppers anonymously on 0800 5555111.