Police say a 19 year old man needed surgery after sustaining two fractures to his jaw following an attack last weekend in Skipton town centre.
It happened on Keighley Road near to the entrance into the bus station at approximately 4.30am on Sunday (31st July).
Officers say the victim was punched in the face, knocking him unconscious to the ground.
He was treated at Airedale General Hospital and then transferred to Bradford Royal Infirmary where he underwent surgery to repair the fractures.
Police are requesting people's assistance to help establish the full circumstances surrounding the incident.
PC Rich Sutcliffe of Skipton Police, who is investigating the incident, said: “This was a particularly nasty and entirely unprovoked assault on a young man who had been enjoying a night out in Skipton with friends.
“He has sustained serious and painful facial injuries which required surgery and will impact his life and his ability to carry out his employment for a number of months whilst he recovers from this.
“While a number of other enquiries are being conducted, I appeal for information from anyone who was in or around the bus station area at this time and may have witnessed any part of this incident.
“Please get in touch with me as soon as you can.”
Anyone with information that could assist the investigation should email email@example.com.
You can also call North Yorkshire Police on 101, select option 2, and ask for PC1728 Rich Sutcliffe. If you wish to remain anonymous, you can pass information to Crimestoppers on 0800 555 111.
Please quote the North Yorkshire Police reference number 12220134253.