The incident was reported just after 3 a.m. on Feb. 6 inside a building on West 184th Street.
The 59-year-old victim entered the building after walking home from work when the unidentified man sprayed him in the face and demanded money.
Authorities say the victim resisted and a struggle ensued.
The suspect ran away in an unknown direction with $5.
The victim suffered irritation to his hands and face and was treated by EMS at the scene.
Anyone with information 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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