I had one run in with these kids. One of the kids wound up like he was going to punch me in the face while I was leaning against a wall smoking a cigarette. I kept a straight face and didn't raise my hands or flinch, hoping he was just trying to get a reaction out of me. He was with two friends. I'm sure if I reacted in any way things would have escalated. I didn't like my odds at 3 on 1 even if they were just kids.
I know other people who had had ugly brushes with them.
Only half of them are in jail, I hope the ones that are still around keep their heads down and trouble us no more.