Police have released a harrowing image of a man left with serious head injuries after being assaulted outside a Ramsbottom pub in a bid to prompt witnesses to come forward.

The picture shows Ian Kennedy, 46, lying unconscious in Salford Royal Hospital, where he has remained in a critical, but stable, condition ever since he was attacked 12 days ago.

The attack took place at around 6.15pm on Saturday, September 12, in an alley to the rear of the Mason Arms Pub in Bolton Road West, Ramsbottom.

The victim was punched once, causing him to fall back and hit his head on the floor.

Police have subsequently arrested four men, aged 25, 22, 20 and 22, who have been bailed until November 9.

Despite these arrests, detectives are still hoping people who witnessed the attack will come forward to assist them with their enquiries.

Detective inspector Stuart Wilkinson said: “I am now appealing directly to those people who witnessed the attack.

“We know there are people out there who saw what happened, but they have not yet come forward.

“I ask these people to look at the picture of poor Ian, who has been lying incapacitated for 12 days, and search their consciences.

“What if this was your brother, your father or your son? You would want people to help.

“Please do the right thing and help us catch the man or men responsible for this awful attack.”

Anyone with information regarding the assault is asked to contact police on 0161 856 3400, 101 or the independent charity Crimestoppers, anonymously, on 0800 555 111.