A police officer was battered with a sledgehammer during a botched raid on a cash machine in the Black Country.
The 41-year-old was one of two officers first to arrive at the Tesco Express store on Hamstead Road, Great Barr, where a gang of three were carrying out the raid on Sunday night.
One of the gang attacked the police car with the hammer, smashing a window and hitting the officer on his head and arm.
The raiders then fled in a dark coloured Audi A6 shortly before midnight.
Chief inspector Havrvi Khatkar said: "Day in day out our officers put their safety on the line to protect the public from some exceptionally dangerous criminals.
"Thankfully in this case the officer escaped major injury, but these were clearly desperate thieves who must be tracked down."
A member of the police force since 2007, the attacked officer, who has not been named, was taken to hospital and later discharged with multiple cuts, bruising, and severe swelling to his face and arm.
The area around the supermarket remained cordoned off as police carried out a forensic examination of the scene.
Items being investigated included tools left by the gang as they fled the scene.
CCTV footage was also collected by detectives in a bid to identify the three men who were wearing dark clothing and face masks.
Chf Insp Khatkar added: "As the gang drove off the boot of the car was open. People who were in the area at the time may remember this,
"I'd urge those people to get in touch along with anyone who saw a dark coloured estate car in the area before the crime."
Last year the Mail revealed nearly 100 officers had been attacked inside police stations across the West Midlands in the previous two years.
And in June last year PC Adam Koch was stabbed twice as he wrestled with a knife-wielding attacker at the Madrassa Qassim Ul Uloom mosque on Washwood Heath Road.
He was later given a bravery award.
Ian Edwards, chair of the West Midlands Police Federation has previously called for tougher sentences for those assaulting police and other emergency workers.
Anyone with information on the raid and attack was urged to contact police on 101 or call Crimestoppers on 0800 555 111.