Suffolk police are looking for the man who held up a 7-Eleven at gunpoint early Saturday morning, and investigators say the suspect is linked to a rash of other robberies in the county.

Authorities say the man was wearing a surgical mask when he entered the convenience store on Broadway Avenue in Holbrook around 2 a.m. Saturday and displayed a handgun. He then fled on foot with cash.

Police confirm that they believe the suspect is linked to four other armed robberies in Suffolk. The hold-ups happened at 7-Eleven stores and gas stations in East Patchogue, Yaphank and Bayport dating back to April 20 -- and the suspect wore a surgical-type mask every time, police say.

In each robbery, detectives say the suspect walked in, pointed a gun at the clerk and took off with money from the register. All of the incidents happened after dark. No injuries have been reported.

Customers at the Holbrook 7-Eleven who spoke to News 12 on Saturday said it's frightening that there's a serial gunpoint robber on the loose in the area.

"It's literally right up the road from where I live," one woman said. "You don't think these things happen around here, but they do."

The suspect is described by Suffolk police as a black man who stands approximately 6 feet tall. Anyone with information is urged to call Suffolk County Crime Stoppers at 1-800-220-TIPS. A $5,000 reward is being offered for information that leads to an arrest.