The robbery happened at the store, located at 964 Merrick Road in Baldwin, at 1 a.m. on Wednesday, Sept. 14, the Nassau County Police Department.
A man approached the cashier's counter with what appeared to be a firearm under his shirt and demanded money from the register, police said.
The suspect then fled the scene, traveling west on Merrick Road with an undisclosed amount of money, NCPD said.
No injuries were reported, according to police.
Police said the suspect is described as being a Black man who is between about 30 and 35 years old and about 5-foot-9 with a medium build.
He was wearing a gray shirt, dark jeans, dark sneakers, a baseball hat, and a face mask, NCPD said.
Detectives asked anyone with information about the incident to call Nassau County Crime Stoppers at 1-800-244-TIPS or to call 911.
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