A 39-year-old man was knocked to the floor and kicked in the head during a “vicious” attack in Preston city centre.
The attack happened at around 2.30am on Sunday on Fishergate, Preston.
The victim was taken to Royal Preston Hospital after he lost a lot of blood at the scene.
Police are appealing for any witnesses who may have seen something in the early hours of Sunday morning.
The 39-year-old had been walking with a friend when was approached by a small group of males.
The main attacked remained at the scene for a few minutes before walking off from the area.
DS Jerry Sturgess of Preston CID said: “This appears to be a vicious attack and I urge anyone with any information at all please to come forward. We are obviously very keen for the males responsible to get in touch.”
The main attacker is described as black, around 20-years-old, 5ft 9ins, of slim build with short hair at the sides and curly on top.
Anyone with information about the incident or about the offenders can contact Preston Police on 101 quoting log reference 214 of June 7.
Alternatively, they can contact Crimestoppers anonymously on 0800 555 111 or online at Crimestoppers-uk.org.