Officers are appealing for witnesses after two men were assaulted in Sainsbury's, White Hart Lane in Chelmsford.
The men attempted to stop three other men, who they believed were shoplifting, from leaving the store at around 2.10pm yesterday.
Both men were assaulted and suffered non-serious injuries.
The assailants then left the store on foot.
All three men have been described as white and being between 20 and 30 years old.
One of the men is stood at around 6ft 4ins tall. He was of a heavy build and wore a grey top and a grey and green baseball cap.
The second man is of a lean build and stood at around 6ft tall. He had short brown hair and wore a grey shirt and jeans.
A third man, described as being of stocky build, and standing at 5ft 6ins tall wore a grey polo shirt.
Anyone with information about this incident is asked to call 101 and speak to the Chelmsford Local Policing Team quoting incident number 636 of 11/07.
Alternatively, you can contact the Crimestoppers charity 100% anonymously on 0800 555 111 or use the anonymous online form at Crimestoppers-uk.org
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