The 2 hour gap? I don’t think anyone knows.
It is possible the shooter, or his now deceased girlfriend, had been engineering students. I think the “mental defective” just decided to take his “mad” out on a whole bunch of innocent people. Something “defectives” are wont to do.
I’ve been following this all day and I’m surprised that nobody has pointed out the total incompetance of the campus police (read, security guards). They tried to contain the whole thing as an isolated dorm incident. It was way over their heads and they should have called in some real policemen who would have stormed the campus and prevented the second shooting.
The concept of a campus police force is stupid in this hollywood and terrorist era.