Dunedin City Council, University of Otago and police sources all said that while the extent of the problem was less than that experienced at last year's Undie 500, that it happened at all was cause for concern.
Dunedin Mayor Peter Chin said yesterday he was "disappointed there were things like that that happened".
Mr Chin had driven through the university area late on Saturday night, and police he spoke to were happy with how the event was unfolding.
"But the Garden's Tavern was a key point," he said, referring to the rock- and bottle-throwing that occurred when a large group of people left the tavern.
He was notified about the problem by police southern district commander Superintendent George Fraser at 4.30am, and by the time he returned at 5.30am, the streets had been cleaned up by Delta Utilities.
The streets were also clear of "half-dead students", in contrast to last year.
There was little which could be done to stop the event, though he would be looking into the cost of liquor sold at the weekend.
"I think this is an event that we don't want to happen, because it fuels things. It proves to me all it is is a booze trip."
University student services director David Richardson said in a press release it was disappointing, given the efforts of the council, police, Fire Service and both local student associations, there had been a repeat of last year's problem.
"There is no doubt the combined efforts of all these agencies resulted in reduced overall levels of disorder during the weekend. However, there is still a lot to be addressed . . . In the end, we remain dependent upon the responsibility of individuals involved to make good decisions."
Asked whether students would face further censure by the university after being dealt with by the courts, university communications manager Brigid Feely said that question would have to be asked later this week, when the university had all the facts.
Otago University Students Association president Simon Wilson emailed students last week drawing attention to the liquor ban put in place for the event, the high risk of arrest for disorder at the weekend and the "terrible effect" on students and the university after last year's Undie 500. Mr Wilson urged students not to break the law.
Yesterday, Mr Wilson said he was disappointed by what had happened, although he was in Castle St on Saturday night and felt the problem was not as bad as last year's.
"There were half the number of arrests, and three times the number of police.
"You can't judge 20,000 students based on the actions of 12 [who were arrested]."
Mr Wilson did not think those arrested should face further censure from the university.
