A shop assistant has been hit in the head with a hammer at a mass brawl which included two wheelchair users in Leatherhead.

The fight broke out between 6pm and 7pm on Sunday, July 25, at Red House Gardens between a group that was at a team-building barbecue and a gang of eight people.

The attackers, including two people in wheelchairs, left after the fight, but one of them came back and hit the 26-year-old Croydon shop assistant in the head with a hammer.

He was treated at Epsom General Hospital for a small cut to his head. His injuries are not life-threatening.

The assailant is described as a white man, of slim build, approximately 5ft 10in tall, aged between 16 and 18 with dark cropped hair. He was wearing jeans, a light coloured t-shirt and possibly a checked shirt over the top.

Investigating officer Detective Constable Nicola Finlayson said: “I cannot stress how seriously we are viewing this incident. This type of assault is totally unacceptable and we simply will not tolerate violence of this kind.

“It was a very warm evening on Sunday night and I am sure there would have been lots of people enjoying the late sun in the recreation park. It is vital we trace everyone who was there as they may have vital information which will further my investigation.

“Officers were on scene within minutes but the suspect had quickly fled. With your help we can identify the person responsible for this assault and ensure he is brought to justice.”

Leatherhead Neighbourhood Sergeant Simon Cox said: “Leatherhead is a great place to live and it is such a shame that one mindless person spoilt a balmy Sunday evening for the rest of the community. However, by working together, we can ensure the person responsible is robustly dealt with.”

Officers are still looking for witnesses who could help the investigation.

Anyone with information should call Detective Constable Nicola Finlayson at Surrey Police on 0845 125 2222 or Crimestoppers, anonymously, on 0800 555 111.