It happened on Friday, January 14 at 12 p.m. on 4th Avenue.
Police say 29-year-old Disheem Riley approached the 79-year-old man, who was using a cane at the time and punched him once in the head.
They say Riley then took off on a scooter leaving the victim lying on the ground.
The victim was treated on the scene for a minor injury to his head.
Riley was arrested and was living at a shelter nearby.
Employees at the homeless shelter saw the video released by police and reported him to the NYPD.
Riley is now facing charges of harassment and assault.
Anyone with information in regard to this incident is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).
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