He was chasing the kid and threw something at him...looked like it was burning. The other guy was beating him on the ground with a skateboard. The third guy pulled a gun on him.
All three were moron anarchists spoiling for trouble, just like the kid was.
I think it is pretty likely the kid is found not guilty due to self defense. Maybe they will get him for weapons violations or something.
None of those four people should have been there doing what they were doing.