Three men were injured in a bar brawl in Chesterfield town centre.
A group of men, two aged 20 and one aged 19, were on the dance floor in the Groove Bar when it is thought one of them may have bumped into another man.
All three men in the group were then punched.
One fell to the floor and suffered two broken teeth and a cut to his chin, one suffered bruising to his eye and lip and the other suffered bruising to his neck.
The incident in the Church Walk venue happened between 4am and 4.30am on Sunday, January 10.
A police probe into the incident is underway.
Officers want to hear from witnesses and are keen to trace two men seen in the bar at the time of the incident.
Both were white and thought to be in aged in their 20s.
One was around 5ft 7ins, with short dark hair. He was wearing dark rimmed glasses and a white jumper with dark coloured stripes.
The second man was around 6ft tall with short or shaved hair and was wearing a white polo shirt.
Anyone with information should contact Derbyshire Police on 101, quoting crime number 1377/16, or call Crimestoppers anonymously on 0800 555 111.