He's already been arrested.
And he was wearing a gas mask, a bulletproof vest, and a black mask. It is said that he resembled Bane from the movie.
Honestly, I think that guy just must've lost it all at once. He seemed like a sane person, pretty bright, with a future planned out. I'm sure a serious and tragic event happened when he was a kid or just recently, causing him to lose his control.
Anyway, the guy's fucking nuts, and I really feel bad for the families involved. I can't imagine how scary that would be. You don't realize it, but that could've happened to anyone, and people are way to materialistic, and they worry about things that shouldn't matter, and they neglect how fragile life really is.