The PSNI is warning of the dangers of organised street fights and reckless bare-knuckle brawls after online footage emerged of people fighting each other.
The scenes appeared on the Northern Ireland Fight Scene' Facebook page which started on October 26 and is asking people to send in clips of fights recorded on mobile phones and cameras.
The disturbing page has already attracted more than 23,000 fans and posts are labelled everything from 'Two 17-year-olds sort it out' to 'Granny Fight in Belfast'.
Among the concerning clips is footage of children and teenagers taking part in organised fights in outdoors spaces, with crowds around them.
There is also footage of random bare-knuckle fights in the street, scrapping in a kebab shop and two older women going toe-to-toe on Royal Avenue in Belfast city centre.
Page administrators urge people to send in footage.
"Let's get true brawl fights sent in, need the footage to show our best fighters. Get them in people," one of the posts says.
Page administrators have had to respond to complaints from so-called "haters" about children being featured on the page.
"So I know you people are hating seeing kids fighting, but that is what is being sent into the page.
"We will put up anything to do with fights. If you have anything better don't be afraid to send it in to the page."
After the PSNI viewed the Facebook page, Chief Inspector Gary Reid told the Belfast Telegraph he wanted anyone who had witnessed an assault or had information about any organised fighting to get in touch.
"We will not tolerate people fighting in public places in a recreational way and anyone caught engaging in this reckless activity will face the consequences of their actions and run the risk of ending up with a criminal record which will impact on the rest of their lives," he said. "These organised fights must stop. What may start off between one or two people can quickly escalate and the potential for serious injury cannot be underestimated.
"Someone will get seriously hurt. Younger children in particular could find themselves being drawn into a situation that is potentially very dangerous."
Chief Inspector Reid wants parents to be aware of where their children are and monitor their online activity.
"We would appeal to parents and guardians to take responsibility and be aware of what their children are up to when they leave the house," he added.
"Parents need to closely monitor the social media internet sites their children are using and talk to them about the dangers of getting caught up in this sort of dangerous and anti-social behaviour.
"Police are committed to making Northern Ireland a safer place to live and work for everyone and we would ask the public to help us by reporting those involved in these fights," he said.
Alliance Party justice spokesman Stewart Dickson MLA described the page as "very disturbing".
"It's extremely grim stuff," he said. "Social media feeds these things. I would like Facebook to examine the page and see what is going on.
"Promotion of fighting is totally unacceptable."
Meanwhile, SDLP deputy leader and policing board member Dolores Kelly was also horrified.
"As the police campaign tells us, One Punch can kill," the MLA said.
"Also the young people featured on this pages are not thinking of the possibility it will diminish their career and life opportunities.
"Anyone who is promoting violence has to be condemned. It's crazy."