Gaaah, why are people always blaming electronic mediums such as tv or video games when things like this are usually the fault of others or the offender? Maybe the kid was being bullied? I'll bet they never even bothered to look at that aspect.
I've been playing games since I was five and violent games since I was 11 (Unless you count various late '90s turn based JRPGs as violent), and yet I don't have the urge to go out and end my life or that of anyone else. Sure, I love to cause a little mayhem and destruction in a pixelated world, but I would gawk in horror at the idea of killing someone in real life (unless in self defense or to protect my friends and family).