Many 'friends' have problems and could be associated with gangs. In fact in inner city high schools its difficult not to have friends outside of gangs. His friend could have been long-time from grade school, neighbor or family associate who made a wrong turn along the way.
Friends can mean playing video games together, going to the mall, or some other casual activity. What I'm saying is that just because he was associated with a gang member doesn't make him a gang banger, or even a sympathizer. Furthermore its obvious he was looking to escape through basketball, which may have been his only option.
And to say he shouldn't be around such kids is not understanding the dynamics of inner city high schools. There just ain't too many options. In fact many kids want to hang out with him for obvious reasons.
This is simply the wrong place at the wrong time, and it could happen to any star athlete (or good kid) anywhere in the USA. All too tragic story being written over and over again.