Two 14-year-old girls were arrested in Belfast after hundreds of young people turned up to watch what is thought to have been a fight prearranged on social media.
Police said they received reports of disturbances in and around Castle Street and Millfield around 5pm on Sunday afternoon.
"Officers responded and as many as perhaps 200 young people were found to be present having apparently been alerted by social media," the force said in a statement.
The two teenagers were arrested for disorderly behaviour. A 34-year-old man was also arrested for possession of an offensive weapon.
A 16-year-old at the scene told the News Letter newspaper: "There's two wee girls fighting. It was all organised [on] Facebook."
A police officer told the newspaper that the youths appeared to have come from "all over Belfast".
Videos uploaded to Facebook on Sunday appear to show two young girls attacking each other while surrounded by a circle of other young people.
Several police cars and a helicopter observed the scene and attempted to prevent the large crowd from gathering, the Belfast Telegraph reported.
Police stressed how dangerous and “frankly stupid this business of prearranging fights is”.
The force said the teenagers taking part were risking not only physical harm but also a criminal record.
"This needs to stop now," the police statement ended.
Local policing chief inspector Robert Murdie said officers would continue to monitor reports of pre-arranged fights and urged parents to make sure they know where their children are and to speak to them about the danger of getting caught up in the fights.
In early May, two males, aged 16 and 18, were arrested after two groups of youths gathered around Somerdale Park and Ingledale Park for a pre-arranged fight, the Belfast Telegraph reported.
Richard James is acting head of news for BuzzFeed Australia and is based in Sydney.
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