A man suffered a head injury after being punched during a fight outside a snooker club in Lancaster.
Police said there was a fight between two men in Squires Pool and Sports Bar on Church Street which resulted in one of them, a 35-year-old local man, being punched.
He fell to the floor causing him to fall unconscious.
It is thought that he suffered a head injury.
PC Jim Buddo from Lancaster Police said: “I am asking anyone who witnessed the assault to come forward.
“We believe that someone may have filmed the incident on their mobile phone so I would appeal to that person in particular to get in contact with the police.”
The fight happened between 5.45pm and 6pm on Tuesday, May 12.
An 18-year-old man from Lancaster was arrested on May 12 but has been bailed pending further enquiries until June 8.
Anyone with information can contact PC 2320 Jim Buddo on 01524 596627 quoting incident reference 1137 of May 12. Alternatively, they can call 101.
Crimestoppers can be contacted anonymously on 0800 555111 or online at Crimestoppers-uk.org.