A group of boys had to be talked off the roof of a south Auckland youth justice facility after overpowering staff and stealing their keys.
An opposition MP says it highlights an ongoing problem at the site and has called for the government to step in.
Six police units and the Fire Service were called to the Korowai Manaaki Youth Justice Residence in Manurewa just before midnight on Friday.
Seven boys had overpowered three night staff in a unit at the centre and taken their keys before escaping onto the roof, according to Child, Youth and Family youth justice support general manager Chris Polaschek.
He said although no one was hurt and there was minimal damage done to the facility, the staff involved had been left "shaken".
"At no stage was there any risk to the public," he said.
The boys were eventually talked down and brought off the roof using a fire ladder at about 1.30am on Saturday.
The Ministry of Social Development is now investigating.
NZ First youth affairs spokesman Darroch Ball said the incident was just the latest in a series at the facility and operators had ignored government warnings about understaffing.
"We understand there are only 10 (staff), well below the minimum 15 required," he said.
"Assaults on staff, escape attempts and mini riots have gone on here for the past few years," he said.
Mr Ball said immediate intervention and further oversight by the minister of social development was needed.
Further comment has been requested from the ministry.