It happened on Monday, Nov. 11 at around 7:15 p.m. in Greenvale, Nassau County Police said.
According to detectives, the man, armed with a black handgun, entered the store located at 90 Northern Boulevard and approached the male salesperson inside, according to police.
The suspect forced the victim into the back room and removed an undetermined number of cellphones from an open safe before fleeing the scene on foot in an unknown direction. No injuries were reported at the scene.
The suspect is described as a black male, about 5-foot-8 with a thin build, wearing all black with a black hoodie, black mask and black gloves.
Detectives requested anyone with information regarding the above incident to call Crime Stoppers at 1-800-244-TIPS. All callers will remain anonymous.
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