A teenager was confronted by a gang of six men and a woman and assaulted following a night out in St Helens.
The 18-year-old was left with a serious facial injury following the attack.
He was walking along the St Helens Linkway with a friend close to the Tesco petrol station when he was approached by the group.
One of the men from the larger group then punched the victim in the face before running off.
He later required hospital treatement for a facial wound following the incident on October 10.
Detectives are checking CCTV from the area and are appealing to anyone with information to come forward.
DC Mick Bowes said: “This was a senseless and unprovoked attack on a young man who had been walking along the road with a friend.
“Although it was late at night it is possible someone might have seen something.
“I would appeal to anyone with information to call the police as you could really help the investigation.”
Anyone with information is asked to call detectives on 0151 777 6812, or Crimestoppers, anonymously, on 0800 555 111.