Police have spoken to two young Auckland men thought to be involved in sex sessions with drunk young girls.
Police have been investigating the group of 17- and 18-year-olds, who call themselves 'Roast Busters' and who have boasted about their exploits on the internet since the group was formed in 2011.
Police say the teenagers started a Facebook page five months ago and have been posting videos and details of girls they got drunk and had sex with in a practice called roasting. The page was taken down at the weekend and all videos have been deleted.
Detective Inspector Bruce Scott says the teenagers, one of whom previously refused to cooperate with police, came forward on Monday afternoon following publicity around the case.
Mr Scott told Radio New Zealand's Checkpoint programme it is too early to say whether this latest development will result in any charges.
Earlier, police said those involved could face rape and sexual violation charges, but they did not have enough evidence to lay charges unless one of the girls makes a complaint.
Mr Scott says police believe some of the girls involved are as young as 13. He says police have identified some victims who didn't consent to the sex, some of whom were underage, but they chose not to give a formal statement to police.
Prime Minister John Key on Monday described as abhorrent the actions of the group. He said as a parent, he finds the issue disturbing and disgusting, and under proposed laws the behaviour would be viewed as cyber-bullying.
An Auckland school attended by one of the teenagers thought to be involved on Monday condemned the lack of action. Green Bay High School says it looks to the law to protect everyone - especially those who are vulnerable because of youth and naivety.
Principal Morag Hutchinson says it is extremely frustrating that the perpetrators can't be held to account when they brag openly about their actions and it is disappointing that the legal system doesn't offer protection for the girls in these cases.
Meanwhile, Rape Crisis says police are sending a disturbing message by not prosecuting the group of young men.
Rape Prevention Education director Kim McGregor told Radio New Zealand's Morning Report programme it seems as though what was being described is rape, because a person who is stupefied, such as by being made drunk, can't give consent.
Ms McGregor says she is sure that if police had information and evidence they would act as quickly as they could.
However, criminal defence lawyer Marie Dyhrberg says police are being very responsible, because it comes down to evidence. She says police could be mindful that they would be putting young people through the court system, facing possible jail time.