Police wearing full riot gear advanced three times on a crowd of about 500 chanting students who threw bottles and rocks at them in Castle St, before the crowd was forced backwards to the University of Otago campus and dispersed about 2am this morning.
Multiple arrests were made in what had been expected to be a relatively trouble-free night after a small turn-out for a rogue Undie 500-style rally from Christchurch on Friday and a quiet day in the student quarter yesterday.
More than 100 police officers rostered on for the weekend, which last year ended in student mayhem involving thousands of people and more than 60 arrests, were unable to contain students who gathered on Castle St to watch a couch fire set just as more young people poured from the Gardens Tavern about 11.50pm last night.
When a police skirmish line was set up around the fire students started danced in the street, chanting "scarfies on the piss" and throwing bottles at police. About 30 minutes later officers donned riot gear as they worked to clear the street.
Dunedin area police commander Inspector Dave Campbell said last night he was "thoroughly disappointed" by what happened.
"We thought the situation was under control, the day had gone quietly, it was pretty low-key, everyone was well behaved. This was definitely unexpected."
When police went in to break up the disorder, they became the entertainment, he said. He blamed the disorder on people drinking too much alcohol.
Asked if he was disappointed the arrival of about 100 Christchurch students in Dunedin on Friday as part of an unofficial Undie 500-style rally (the official 2008 Undie 500 was canned after last year's events) had apparently sparked another night of chaos Insp Campbell said he was not sure if those people were to blame.
"I don't know that we can blame Canterbury students for this one. There was only a small number of Canterbury students here. We may have to look at Otago students this time."
