An unhinged attacker stabbed a man in an unprovoked assault on a Bronx street, police said. 

The 59-year-old victim was on Sedgwick Avenue near West 179th Street in Morris Heights around 10:30 p.m. May 22 when the suspect suddenly stabbed him in the head and torso with an “unknown object,” cops said late Monday. 

The victim was taken to St. Barnabas Hospital, where he remains in serious condition. 

Police are still searching for the assailant – believed to be a homeless “emotionally disturbed person,” cops said. 

Video released by the NYPD shows him apparently exiting a park and then walking on the sidewalk.