So, is there a back story here, or did you just need to post something?
They arrested 4 “teens” out of 20 to a 100 involved.
The back-story seems to be that the ‘rampaging youths’ were all blacks yelling racial epithets, and the victims were all mostly white. The Philly Media is keeping a lid on it, but eye-witness accounts are trickling out in the social media.