Official or not, Undie 500 weekend erupted into violence on the streets of Dunedin's student quarter for the second year running on Saturday night.
Police said Canterbury students were not to blame this time and pointed the finger at Otago students and a group of non-students drawn by the "magnet" of expected trouble.
A much-reduced and unofficial Undie 500 contingent made the trip from Canterbury University to Dunedin on Friday.
However, only three Canterbury students were arrested during an incident on Castle Street, Dunedin, where police in riot-gear had to disperse over 300 bottle-throwing partygoers.
Another 21 were arrested. About half were Otago students and half non-student Dunedin locals.
Dunedin Area Commander Inspector Dave Campbell said 100 extra police had been rostered on, and until midnight on Saturday the weekend appeared to be passing without incident.
Just before midnight, a couch was set on fire at one end of Castle Street attracting a large crowd. Shortly after, the student pub Gardies The Gardens Tavern closed, disgorging hundreds of students on to Castle Street. Many found their route into the city blocked by those assembled for the couch fire and joined them.
Rocks and bottles were thrown when police tried to disperse the large crowd and officers retreated and then returned wearing riot-gear and carrying perspex shields. Several small fires were lit and a makeshift bomb blew up a letterbox.
Officers blocked sidestreets to prevent more students from joining and then charged the crowd three times. It took until 2am to disperse the crowd, with officers taking hits from bottles and rocks on their riot shields.
Campbell said the Undie 500 was not the catalyst for the trouble. "There was a very small number of painted vehicles and we understand quite a few of them went through to Queenstown for skiing," he said.
What was noticeable to police, students and Campus Watch officials was the number of non-students present, he said.
"It's quite clear that it (the Undie 500) is seen as a magnet."
The nine non-students arrested during the couch-fire incident were aged 16 to 33, not the typical university student profiles, he said.
"It's much improved on last year. Our belief has been student behaviour is improving, but it's still far from acceptable."
Dunedin Mayor Peter Chin disagreed with the police evaluation, saying the Undie 500 was the cause of the weekend mayhem and deserved the blame.
"It's a booze trip. It does have something to do with it."
Chin said the event drew the crowds and the organisers were unable to control who took part or what they did. The event was also tacitly supported by adults and retailers who catered for it and offered "massively discounted" alcohol, he said.
Ensoc President Graeme Walker said it was frustrating to see the university's engineering society and Undie 500 brands being associated with the riots as "we had done all we could to distance ourselves from this year's trip". The binge-drinking culture in Dunedin was "more accepted, and even glorified" by scarfies.
Canterbury University Students Association president Michael Goldstein and his Otago University counterpart, Simon Wilson, said media hype had drawn troublemakers and onlookers to the event. Of the 300-strong Castle Street crowd, half were "just looking". While the vast majority of the crowd were students, it was salient that the arrest figures were almost half non-students.
Otago University Student Services director David Richardson said the incident was "disappointing". Agencies including police, council, fire service and student associations had tried hard to avoid a repeat of last year's problems.
"There is no doubt the combined efforts of all these agencies resulted in reduced overall levels of disorder," he said. "In the end, we remain dependent upon the responsibility of individuals involved."
Narelle Suisted and Matt Maguire followed the Undie 500.
- The Press