Video shows one of the suspects pointing a gun at customers in John's Fried Chicken on West 207 Street in Inwood.
It happened on Sunday, March 6, around 8:15 p.m.
Police say the armed suspect had arrived with another man on a blue motorbike.
The suspects fled with the victim's necklace, which had a pendant featuring the numbers "72."
No shots were fired.
The gunmen took off on the motorbike westbound, on the sidewalk on West 207th Street, towards Sherman Avenue.
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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