A man had part of his left ear bitten off after being attacked in central Brighton.
The 24-year-old victim was near the junction of New Road and North Street in Brighton, when the incident happened.
He was taken to the Royal Sussex County Hospital in Brighton following the attack.
Detective Constable Christopher Hike, of Brighton CID, said: "This was a nasty incident in which the victim sustained permanent injuries to his ear and had to undergo emergency surgery."
Two men were responsible for the attack.
Anyone with information about the incident, which happeed at around 12.30am on Saturday, March 30, is asked to call Sussex Police on 101 or email firstname.lastname@example.org, quoting serial 0057 of 30/3.
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