From Fox News

Gelman was wrestled to the ground by three cops and the man he slashed, ending a 28-hour rampage
From what I have seen on the news and in an interview with "the man he slashed" on the subway, it was that victim that did most of the wrestling, not the police. He fought off the BG after he was attacked on the subway and the police came in afterward to detain and arrest him. He did however receive nasty wounds as you would expect from a knife fight.

Yup, the cops were minutes away when seconds count (for this guy at least, the other victims were shit out of luck) and another ordinary citizen/victim stopped the BG. But only cops should have guns............