Robbers left their victim with stab wounds and a broken jaw as they striped of him electric scooter and other possessions in Coventry.
Police were called to the incident on St James Lane, Willenhall around 8pm on 16 February.
The robbery is thought to have happened near the Simply Local store, formerly The White Bear pub.
The victim was stopped by four teenagers who beat him to the ground and stabbed him before making off with his scooter and personal items.
Police are asking anyone with information regarding the violent attack to get in touch.
West Midlands Police said: “We were called after a man in his 40s was robbed in St James Lane, Willenhall, Coventry, at about 8.10pm on Tuesday 16 February.
“We believe he was stopped by a group of four teenagers and punched, knocking him to the ground.
“He suffered a stab wound to his side and a broken jaw which were treated at hospital and thankfully are not believed to be life-changing.
“An electric scooter and personal belongings were taken but have since been returned to the victim.
“Anyone with information can message us via live chat at west-midlands.police.uk, or call 101. Alternatively to remain completely anonymous contact Crimestoppers on 0800 555 11. Please quote crime reference number 20CV/45653H/21.”
West Midlands Ambulance Service said: “We were called to reports of an assault at 8.09pm on 16 February.
“One ambulance, a paramedic officer and the Warwickshire and Northamptonshire Air Ambulance attended the scene.
“On arrival we discovered one patient, a man, who was treated for serious injuries before being taken to University Hospital Coventry and Warwickshire for further treatment.”
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