Some of the crowd spilled out into Castle St and there was some broken glass in the area.
Several members of the University of Otago Campus Watch observed the gathering and police also visited the area.
A police spokeswoman said police had attended, the group had soon dispersed and there had been no arrests, she said.
A chair fire on a footpath was extinguished near a flat in Leith St, after a fire appliance from the Willowbank fire station attended following an alert at 12.41pm.
Willowbank Station Officer Ant O’Neill said people nearby had put the fire out themselves using water buckets, when asked by firefighters.
Firefighters had earlier in the day extinguished a burning couch elsewhere in Leith St after being alerted to it at 6.52am.
It was "frustrating" that Fire and Emergency New Zealand staff were being diverted from other, more important duties by such fires, Mr O’Neill said.