He walked into the 7-Eleven store on Sheppard Lane in Nesconset early Tuesday, pointed a gun at the clerk and robbed the place, police said.
Now, Suffolk County police has released surveillance images from that robbery -- and is asking your help in catching the man responsible.
The armed robbery took place at about 12:30 a.m., police said. No one was injured.
It was not immediately clear how much money was taken.
Police said the man, described as being in his 30s, about 6-foot-2, 230 pounds, with a muscular build and a goatee, wore a blue T-shirt, cargo shorts and a black hat. He fled the scene on foot.
Police are asking anyone with information to call Crime Stoppers at 800-220-TIPS. All calls will remain confidential. Callers are eligible for a cash reward of up to $5,000 for information leading to an arrest.