We're investigating a robbery which took place in Chippenham town centre.
At approximately 8.40pm on Friday 8 September, a 17-year-old male was stood next to his moped in the car park near to Tesco Metro at the rear of Emery Gate.
Three men, believed to be aged in their late teens to early twenties, approached the 17-year-old and demanded he hand over his mobile phone. One of the men then punched the victim in the face causing minor bruising.
The victim then handed over his phone - a gold iPhone 5s.
The suspect is described as white, approximately 6 ft tall, of slim build with blonde facial stubble. He was wearing a grey beanie hat and a dark coloured tracksuit.
Detective Constable Gemma Lumley, of Central CID, said: "The victim was left really upset by this incident - fortunately, he wasn't seriously injured but was left really shaken by what happened.
"We are carrying out a really detailed investigation into this incident which took place in the town centre - it is likely there would have been people about at the time.
"I'd like to appeal to any witnesses or anyone who may have seen the group prior to or after the incident, as well as anybody who may recognise the suspect from the description, to get in touch via 101."
Information can also be left anonymously with Crimestoppers on 0800 555 111.