In my previous company, one candidate became belligerent and physically pushed interviewer away from whiteboard after interviewer told him that his solution is

In my previous company, one candidate became belligerent and physically pushed interviewer away from whiteboard after interviewer told him that his solution is not correct. Interviewer asked candidate to wait a few minutes, left room, called recruiter who in turn called security to escort candidate out. My desk was just outside interviewing room and I saw the long glance that the guy gave to interviewer - it was "if i see you again, I will kill you". Or at least I interpreted it that way. Company (and interviewer) decided not to bring charges so I assume he continues to interview at other places. There are non-zero number of unstable individuals who do not handle rejections or criticism well.