Shocking CCTV shows the moment a traffic officer was left seriously injured after being mauled - by a POLICE DOG.

The cop was left requiring surgery after being savaged by the out-of-control hound as he was trying to apprehend a suspected car thief.

Dramatic footage captured the horror as it unfolded on Leighs Road in Shelfield, Walsall, West Mids., in the early hours of Tuesday (11/4).

The officer had been trying to capture the suspect on foot after he abandoned a stolen car near an alleyway following a ten mile car chase from Cannock, Staffs.

But when he returned to the vehicle to check for any other passengers he was set upon by a police dog released by its handler.

The officer can be seen being dragged to the ground by the mutt before the dog handler and other officers rushed to his aid as the suspect got away.

West Midlands Police has now launched an investigation into the matter as their officer remains in hospital.

A force spokesperson said: "One of our traffic officers was bitten by a police dog from our West Midlands Police Dog Unit following the pursuit of a stolen car which started in the Cannock area of Staffordshire and ended in Leighs Road, Shelfield.

"A stinger was deployed and the vehicle was stopped.

"The officer got out of the vehicle to give chase to a man who ran from the car and was bitten.

"No arrests were made.

"The officer was quickly rushed to hospital where he received treatment for cuts and bites received in the attack.

"The officer was taken to hospital after sustaining cuts to his upper left. He underwent surgery and is currently in hospital.

"Our Professional Standards Department has been informed of the incident and as with all dog bites, an internal investigation will take place."