Tonight police arrested a 27-year-old man who they say has been fatally stabbing people in Brooklyn.

Police say Daniel St. Hubert—who was paroled less than two weeks ago after serving seven years for attempted murder and several felony-assault charges—was only out of jail for a week before he attacked 18-year-old Tanaya Grant-Copeland, who was stabbed at least 32 times and left dying on the street.

Just two days later, police say St. Hubert struck again, this time accosting two children in an elevator with a knife. The kids, aged six and seven, were headed out to get ice cream, when St. Hubert began stabbing them.

One child was pronounced dead; the other remains in critical condition. Police say the same knife was used in both attacks.

The cops were evidently able to track down St. Hubert through DNA evidence pulled from the murder weapon.