New Zealand police are investigating a group that calls itself the “Roast Busters,” whose members boast about getting underage girls drunk to engage in group sex, and then shame the victims on social media.

The group of 17 and 18 year old boys from Auckland, created a Facebook page to brag about their conquests. Police say the boys have been operating since 2011, but were unable to charge them because none of their victims made a formal complaint, according to a report in the New Zealand Herald.

The group’s Facebook page has since been removed.

New Zealand Prime Minister John Key called the behavior "abhorrent", but said it was difficult to prosecute without evidence, according to a Sky News report.

One underage girl, her identity obscured, told TV3 in New Zealand, that the group preyed on her after giving her so much alcohol she blacked out.

"You could say I got raped. I had sex with three guys at one time," she said.

"It's just extremely disturbing and disgusting behavior and these young guys should grow up,” Key told reporters.

Since the story broke, one of the group’s founders-- who has not been identified—apologized on Facebook, saying he made some "major mistakes" and had tried to make "dramatic changes" to his life.

"I have not been happy with who I have become and if I suffer any consequences from my past actions then I guess I deserve it but… I am a good person at heart and I have matured and taken this as a massive learning experience. All the girls that have been effected by this whole ridiculousness I apologize and wish the best for you."

Another boy-- Joseph Levall Parker, son of Hollywood actor Anthony Ray Parker—was fired from his real estate job this week for his “despicable behavior,” after the scandal made national headlines. Parker’s father, Anthony Ray, appeared in The Matrix, among other films. The actor’s New Zealand agent, Gail Cowan, said he wanted privacy and "has no interest in speaking to the media."

Two group members have reportedly come forward to police.

Dr. Kim McGregor from New Zealand’s Rape Prevention Education Group hopes police will find a way to take action quickly against the boys.

"It's not just that they are wanting to have sex with women, they're wanting to humiliate women - that's a real concern. They are getting these young women drunk and we know that if someone is stupefied then they cannot consent, so therefore it would be rape,“ she told Radio New Zealand.

The Herald reported that at least one of the girls involved with the group has attempted suicide.

"We're hoping that somebody will be brave enough to make a complaint to us, formalize it," Detective Inspector Bruce Scott told Radio New Zealand.

"Once one young lady does, well we're hopeful that others will see that she's been brave enough and come forward as well."

It’s not clear how many people are part of the “Roast Busters” group, but Parker and another young man-- Beraiah Hales -- boasted of their involvement in a video posted online.

Police confirmed that one of the members was the son of a police officer. Cops have been monitoring the Roast Busters' Facebook page for two years and have been in touch with the members’ schools, but didn’t close it down for "operational and tactical reasons.”

"Whilst we acknowledge it was upsetting for the victims, it was being monitored for information or evidence that would assist our investigation,” Scott said.

Scott also told a local TV station that the fact that one of those involved in the Roast Busters' page was the son of a police officer had not influenced the inquiry or the decision not to prosecute.

A vigilante group has been set up on Facebook calling for action. One man involved said there were at least 50 "irate, angry fathers" ready to dish out their own brand of justice. He said feeling in the community was so strong that he had received calls from gang members wanting to get involved.

Click for more from the New Zealand Herald.

Click for more from Sky News.