A man was verbally abused then knocked to the floor outside a York takeaway.
The assault happened between about 1.30am and 1.45am on Saturday (June 23) on Clarence Street.
The victim, a 39-year-old local man, was standing outside Pizza Dela Sosa talking to a woman he had just met.
They were approached by a couple who verbally abused them before the male suspect hit the victim twice, to the back and the side of the head.
He was knocked to the floor and suffered a significant injury to his lip requiring stitches.
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A North Yorkshire Police spokeswoman said: “We are requesting the public’s assistance to help establish the full circumstances surrounding the incident.
“In particular, we are appealing for information in relation to the identity of the female who was speaking with the victim at the time of the assault.”
Anyone with information that could assist the investigation should contact North Yorkshire Police.