Police had to shut down several parties in Dunedin at the weekend and officers are reviewing CCTV footage to help them work out who struck a student with a bottle at one of them.
Senior Sergeant Craig Dinnissen, of Dunedin, said police had a heightened presence in the student quarter and they came across a large party on Saturday night.
The victim of the incident with the bottle suffered "moderate injuries".
Detectives hoped CCTV footage from the area would help them identify the offender.
Officers estimated about 100 people were at the party and it was one of several in the area that they shut down.
Gatherings of more than 10 people were forbidden under Covid-19 restrictions that applied under Alert Level 2. The restrictions were designed to stop the coronavirus from spreading.
Snr Sgt Dinnissen said people at the gatherings were putting themselves and others at risk.
A fight also broke out in Castle St.
