The 14-year-old victim was walking from Tesco Express, Old Farm Park, across a bridge, near to a playing field at 10pm, when he was approached by four boys. The boys demanded the victim’s personal belongings and assaulted him.

He was punched in the face, head-butted and then hit on the leg with a piece of wood. The offenders grabbed his bag and mobile phone and ran off.

The offenders are all black, aged in their late teens and between 5ft 9ins and 6ft. The first is of average build and was wearing a black beanie hat and black tracksuit bottoms. He was not wearing any clothing on the top half of his body.

The second offender is of average build, has long, black, dreadlock-styled hair, which was tied back in a ponytail, and he was wearing a multi-coloured T-shirt and dark blue jeans.

The third offender is slim and was wearing a light blue T-shirt. The fourth is stocky, has a shaved head and was wearing a hooded top and blue jeans.

The bag which was stolen has BCM Planet Dance Magalluf written on it and police are appealing for anyone who has seen this bag, witnessed the incident or has any information to contact them.

Anyone with information is urged to contact Det Con Adam Billingham at Milton Keynes police station. He can be contacted via the 24-hour Police Enquiry Centre on 0845 8 505 505. If you do not want to talk to the police, call the Crimestoppers charity anonymously on 0800 555 111.