The suspect was caught on camera before and after the robbery in the Fordham section on Wednesday.
Police say he followed the boy into his apartment, where he threw the 9-year old against the wall and took his money.
The man then rode away on a bike.
The suspect is described a black man in his 50s, wearing a red shirt, dark shorts and white sneakers.
Anyone with information in regards to this robbery is asked to call the NYPD's Crime Stoppers Hotline at 800-577-TIPS. You can also submit their tips by logging onto the Crime Stoppers Website at www.nypdcrimestoppers.com or texting tips to 274637(CRIMES) then enter TIP577.
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