A man was taken to hospital after being assaulted by another close to York Minster.
The incident happened at about 2.45am on Tuesday, 8 January in Duncombe Place, and involved three men.
Two men had a verbal altercation, which resulted in one of the men physically assaulting another, knocking him to the ground.
The victim, aged 19-year-old, was taken to hospital by ambulance where he was treated for facial injuries. He had to return to hospital the following day with symptoms of concussion.
Officers want to speak to the man in the image in connection with the incident as they believe he may have information which can assist the investigation.
Anyone who recognises the man in the CCTV image, or who has any information, is asked to contact North Yorkshire Police.
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