"Throughout this afternoon and this evening a considerable amount of students were congregated at this one location," said Mr Ure.
"A 21-year-old male was arrested for an assault on a female at 3.30pm.
"There was a second arrest of a male for disorderly behaviour.
"The party was voluntarily closed down around 6pm and people dispersed."
A witness said a three-storey building was overloaded and people had spilled on to the street.
He said the party has been going all day.
A spokesman for St John Ambulance said "a female was punched in the face and taken to Dunedin Hospital with minor injuries".
The Fire Service had been called over concerns about the number of people in the building and on the street.
Mr Ure said police were speaking with the occupants to address safety concerns.
ODT
[NZME-NZG-NZC]
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