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Police and student representatives say they are "thoroughly disappointed" after another round of Undie 500 disorder in Dunedin over the weekend resulted in 30 arrests.
Riot police clashed with a crowd in the student stronghold of Castle St in the early hours of Sunday morning, following a trouble-free day as students associated with the Christchurch to Dunedin car rally partied around the city.
The official Undie 500, organised by Canterbury University engineering students, was cancelled after last year's riots and 69 arrests.
However, an unofficial version of the event ran, with about 40 carloads of students arriving in Dunedin on Friday night.
Over the weekend police arrested 12 students from Otago University, two from Otago Polytechnic, three from the University of Canterbury, and 13 non-students, with the bulk of the trouble occurring late on Saturday night.
Most are bailed to appear on disorder charges in Dunedin District Court on Thursday.
"I don't know that we can blame Canterbury students for this one. We may have to look at Otago students this time," Dunedin area police commander Inspector Dave Campbell told the Otago Daily Times. He said he was "thoroughly disappointed" by what had happened.
His sentiments were echoed by Otago University Students' Association president Simon Wilson.
"It was much better than last year (but) I'm not happy - the day was developing well, it looked very much like nothing was going to happen," he said.
Fires lit in the streets sparked Saturday's disorder.
A temporary liquor ban put in place by Dunedin City Council had been working, but as people left the Gardens Tavern, they went to flats and got bottles and rocks, Mr Campbell said.
Police were unable to contain those who gathered on Castle St to watch a couch fire about 11.50pm, just as more people arrived from the tavern.
When a police skirmish line was set up around the fire, a tense situation developed.
The crowd of about 300 was finally dispersed about 2am yesterday.
About 100 extra police were in the city from Invercargill and Christchurch to support the Dunedin officers.
Students from Canterbury said they were looking to have a low-key night so that the official Undie 500 could return next year.
- NZPA