The attack happened just before 10 p.m. last Sunday on Pleasant Avenue in East Harlem.
According to the NYPD, the suspect got into an argument with a 67-year-old man before striking him in the head and back with the pipe. Officials say the suspect then fled the scene heading south on Pleasant Avenue.
First responders transported the victim, who suffered minor injuries, to a hospital in stable condition.
The suspect is described as a man with a medium build and between 5 feet 10 inches and 6 feet 1 inch tall. He was last seen wearing a black sweatshirt, gray sweatpants and black sneakers.
Anyone with information about the attack is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477).
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