Moment flash mob of teens beat each other up in Philadelphia

Widespread disorder, believed to have been planned on social media, led to more than 30 arrests in the center of Philadelphia.
Large groups, believed to be mainly youths, formed a flash mob on Monday evening, with many brawls breaking out.
The city's police commissioner has branded the gathering 'idiotic'. Officers believe a war of words broke out on social media, prompting large groups to spill out into the streets.
In one instance, a group of girls were sprayed with mace.
It is thought some could face serious charges after violent attacks.
Police Commissioner Richard Ross told CBS: 'They were actually beaten, maced and claim to have even been tased.
'We know they were assaulted for sure. We had four people, we do not know if charges will be approved on those four. So we’re trying to wait to see, but the whole thing is just idiotic.'
Equally unimpressed was SEPTA’s Police Chief Thomas Nestel, who tweeted: 'SEEKING HELP! Please know what your nugget of love is doing after school. Kids are hurting kids. Love them by making them come home.'
He said the fights were the worst he had ever seen.
A female police officer was injured when she fell off her bike during the response to the flash mob chaos.