A knife-wielding man was shot and killed by police after allegedly stabbing a student in Brooklyn.

Police say the suspect, 49-year-old Calvin Peters, was emotionally disturbed and had a documented history of mental illness. Video taken inside the Chabad Lubavitch Hasidic Headquarters in Crown Heights at around 1:45 a.m. shows Peters with a knife that he had allegedly just used to stab a 22-year-old man in the head.

News 12 has learned that a witness ran outside after the stabbing to alert officers.

Police then went inside and told Peters to drop the knife, and it appears that he did. They say he later picked it up and lunged at an officer, who fired one shot.

Peters was hit in the chest and pronounced dead at Kings County Hospital.

The stabbing victim is reported to be in stable condition.