A number of people were serioulsy injured in what police described as a “large scale disturbance” outside a pub.
Officers are appealing for witnesses to come forward after several people were hurt in the incident outside the James Tassie pub on Kilmarnock Road, Glasgow.
Emergency services were called to the scene shortly after midnight, with three men – all aged 21, taken to hospital.
Police Scotland confirmed an 18-year-old male had been arrested in connection with the incident, and that their inquiries were ongoing.
Detective Sergeant Nikki McPherson of Cathcart CID, said: “We are still trying to establish exactly what happened here. A number of people were seriously injured and it is vital that we make sure we trace all those responsible.
“Our officers are currently going through CCTV and have spoken to a number of people who witnessed the incident, however we are appealing to anyone, who has not already spoken to police, who may have information to get in touch.
“Violence will not be tolerated and although this appears to have been an altercation between two groups, other members of the public could have been caught up in this.
“We would also ask anyone who may have been injured last night, and has not presented themselves to police or attended hospital at a later point, to get in contact.”