The suspect allegedly struck at least five times since July.
The first instance happened on July 16th at around 8:30 p.m. inside of 66 West 88th Street.
The suspect was armed with a knife and approached the 16-year-old male victim in the elevator of the building and demanded money.
The second happened on October 4th at 7:15 p.m. inside of 788 Columbus Avenue.
The suspect, armed with a knife, approached the 55-year-old man in the elevator of the building and demanded money.
The third robbery happened on October 8th at 9 p.m. inside of 303 West 18th Street.
The suspect approached the 25-year-old man with a knife and demanded money.
The fourth instance happened on October 19th at 8:40 p.m. inside of 341 West 24 Street.
The suspect approached a 36-year-old man with a knife and demanded money.
The most recent robbery happened on October 22nd at 7:50 p.m. inside of 60 West 104th Street.
The suspect approached the 40-year-old victim with a knife and demanded money.
In each incident the suspect fled the location on foot.
The suspect is described as Black male, 30-40 years old, about 5'9" tall, and weighs about 190 lbs.
In each incident he was wearing a black jacket, black pants, and a black hat.
Anyone with information in regards to this incident is asked to call Crime Stoppers at 1-800-577-TIPS (8477).
You can also submit your tips by logging onto Crime Stoppers' website at www.NYPDCRIMESTOPPERS.com or by texting your tips to CRIMES (274637), and then entering TIP577.
All calls are strictly confidential.