Seven people have been arrested following a mass brawl in Bexley which left two people needing hospital treatment.
The males, aged between 15 and 21, were taken to south London police stations after fight in Northumberland Heath, which involved up to 100 people.
Footage of the incident posted to social media showed some youths armed with sticks.
Some of the officers called to the scene were from the Metropolitan Police’s Territorial Support Group, which deals with serious public disorder and rioting.
A local resident, who did not want to be named, said she was "shocked" to see children in school uniform involved in the fracas.
"This is the first time for a long, long while that we've had gang-related problems round here," she said.
"They were all youngsters, a lot of them were in school uniform - that was the shock, seeing them in the uniforms.
"They're still youngsters - it's quite a shock when they're all en masse like that, I didn't want to go outside."
She said the police were on the scene quickly and the group started shouting abuse at the officers.
"We don't know what it was over or why it even began - it's crazy," she added.
A Met Police spokesman said: "Officers from the borough and the Met's Territorial Support Group were called to the scene.
"Two individuals suffered non-life threatening injuries. They were taken to a south London hospital by London Ambulance Service to be treated for their injuries.
"Officers are still in the area to provide reassurance."
