A man was taken to hospital after a fight outside a restaurant in Belsize Park.
Police were called at about 6.15pm on Saturday to reports of an assault in the street outside Retsina in Belsize Lane.
The victim, a 41-year-old man who had earlier been escorted from a private party at the Greek eaterie, was punched in the face before the suspect made off along Belsize Terrace.
The suspect was white, aged about 25 to 30, 5ft 7in tall, with short brown hair.
Officers said the victim was taken to hospital but his injuries were not life threatening.
No arrests have been made.
Officers from Camden CID are investigating.
Anyone with information is asked to call police on 101, or Crimestoppers anonymously on 0800 555 111, or visit crimestoppers-uk.org.
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