A man has undergone surgery after he was assaulted following a night out in Wolverhampton.
The 20-year-old man from West Bromwich was attacked as he walked with a friend in Queens Square at 0230 BST on Friday.
He was on his way home from Kipps Wine Bar in North Street when it happened.
The victim was taken to a hospital in Birmingham with serious head injuries and his condition is described as critical.
Detective Sergeant Paul Jones, from Bilston CID, said: "This was a nasty attack on a young man who was out enjoying himself in the city.
"As yet we have no idea what sparked the incident."
Police are studying CCTV footage and are urging anyone with information to contact them.