The incident happened just before 2 a.m. Monday, Feb. 13, in Syosset at the BP station on South Oyster Bay Road, according to Nassau County Police.
Detectives said a man walked into the store with his hand inside his pocket and threatened that he had a gun. He then demanded cash from the 23-year-old employee, police said.
The employee complied and gave the suspect an unknown amount of cash.
Police said the suspect then fled the store in an unknown direction. He is described as 6 feet tall with an average build, and was wearing a black ski mask at the time.
Anyone with information is asked to contact Nassau County Crime Stoppers at 1-800-244-TIPS or call 911. All callers will remain anonymous.
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