Facebook has removed an Australian boys-only group with nearly 7,000 members after “revenge pornography” of an underage woman was allegedly posted to it.

The page, “Melb Guy Pals” was created on Wednesday evening, amassing at least 6,700 members before it was removed late the next day.

The group’s description on Facebook previously read, “talk shit about any girl you want, stays between the boys … can organise fights in this chat but keep it peaceful”.

Pages seen by Guardian Australia showed explicit and targeted posts about young women.

One boy posted that if he got “75 love reacts” on his post, he would “drop mine [sic] and my ex sex tape”. In the comments, other members egged him on, telling him to “pay up”.

The boy later posted: “this video is going up for 20 seconds, you don’t see it, you lose”, and, “I can’t believe I just posted that”. At that point the group had fewer than 1,500 followers.

The girl allegedly in the video was younger than 18.

Other posts tagged girls and young women, calling them “whores” and “fat”, and received positive responses in the comments.

“Holocaust #2 but instead of jews we target women,” one boy said.

Multiple users who reported the page received an automated notification from Facebook saying the page would not be removed.

“Melb Guy Pals was reviewed and there was content in the group that doesn’t follow our community standards. We removed that specific content … instead of the entire group,” the notification read.

However, after Guardian Australia approached the company for comment, the page was removed.

“We absolutely do not allow content that attempts to exploit, degrade or shame anyone, especially young people, and have removed this group for violating our community standards,” a spokesperson said.

After the original page was taken down, a number of copycat groups claiming to be “Melb guy pals 2.0” emerged, which had attracted several hundred members on Friday morning.

The messages on the original page were largely targeted at members of the female-only Facebook advice group, Melbourne Gal Pals.

Once it became clear women and girls from that group were aware of the offensive posts of Melb Guy Pals, one young man wrote, “From now on no sex tapes or anything to do with the general, we want to keep this clean and not have people harassing us 24/7.”

Another posted, “Gal pals want to get police envoled [sic]. How about we just spam nice things and make it seem like they’re making everything up”.

A number of the men posting on the page also had posts raising awareness for suicide prevention and anti-bullying on their personal Facebook profiles.

Sian Moore, an administrator of Melbourne Gal Pals, said police needed to take action.

“A slap on the wrist from their parents or Facebook is not enough. The police and the law need to come down hard on these boys.

“These girls have been victimised and targeted. It needs to be taken seriously by the police and not just a warning because this is revenge porn, this has happened before and clearly the message hasn’t gotten through.”

Moore said all the people in the group were part of the problem, not just those posting.

“It’s like at school if you see a kid getting picked on in the playground and you just stand there, and you don’t do anything. You’re a bystander and you’re just as bad because you’re enabling this behaviour … there are boys that are in this group that are just watching it happen.”

Some young men posted in the group admonishing the behaviour of its members.

“What if it was your future daughter and you had boys posting her ... It also doesn’t matter if it didn’t have her name or her face… it’s still pretty fucked [and] those who did the wrong need to take responsibility,” one boy posted.

Eighteen-year-old Jessica, who asked that her real name not be used, said she knew several of the boys posting in the group.

“It’s awful to think that these people are friends with my friends and I’ve socialised with them before … I can’t even describe how mad I was when I first saw it.”

Jessica said she was the victim of a similar situation when she was 17.

“A boy videotaped us having sex without me knowing, and then showed people around my high school. The school actually found out before I did and made me contact the police. He basically got away with a slap on the wrist,” she said.

“When I saw that group I was shaking and I couldn’t sleep … I tried to find out who the girl was all night, because I know exactly how she was feeling.”

“Revenge porn” is a name given to nude or sexually explicit videos or images of a person shared without consent. These are often obtained by a partner and distributed after a relationship has ended. Victoria has specific legislation making this a criminal offence, which carries a maximum of two years’ imprisonment.

If the person in the video is underage, laws against child sexual abuse material also come into play, which can carry jail terms of up to 10 years.

Louise Moore, another administrator of Melbourne Gal Pals, said the situation had been tough, but had united young women in Melbourne.

“Seeing thousands of girls come together, it’s kind of a silver lining in it … all of the comments [about the girls who were targeted] were just so protective and uplifting.

“We are all supporting each other.”

Guardian Australia understands the posts have been reported to Victoria police. The police have been contacted for further information.