Shocking footage has emerged, showing adults seemingly cheering on students in school uniforms brawling, in the latest incident in Sydney's bullying scourge.
Several after-school brawls in the western Sydney suburb of Bidwill on Thursday afternoon appeared to be adjudicated by adults.
The same vision later shows the grown-ups engaging in their own fights.
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"It's disgusting behaviour and police won't tolerate that behaviour," Superintendent Brendan Gorman said.
The appalling footage depicts one of several physical fights alleged to have occurred across Mt Druitt this week.
Police are investigating several tit-for-tat assaults, including one filmed at a bus interchange on Monday, allegedly involving the same warring teenagers.
"Violence is no way to resolve any conflict," Gorman said.
"If there's any concerns regarding any behaviour, about childrens' welfare, contact the police and we can provide advice."
Youth organisations like Learning Ground believe more support is needed.
"When there is strong investment and strong funding then we will see less of this behaviour," Dr Rumbi Mabambe from Learning Ground Bidwill said.
Two girls, aged 15 and 16, as well as a 25-year-old woman have been charged over the Bidwill brawl.
Police are using the footage to pinpoint others involved.
"If adults are encouraging kids to commit offences they are subject to charges themselves," Gorman said.
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