WEST BABYLON, N.Y. (CBSNewYork) — Police are investigating two more knifepoint robberies on Long Island that they say may be connected to a series of similar crimes.

Around 1:48 p.m. Tuesday, Suffolk County police say a man armed with a knife walked into The Barn on Belmont Avenue in West Babylon and demanded cash. He then fled with an undisclosed amount of money, police said.

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Hours later in Merrick, Nassau County police say a man armed with a large kitchen knife held up two employees at a Game Stop on Sunrise Highway just before 9 p.m. Tuesday.

Investigators believe the suspect in both robberies Tuesday is the same man targeting stores throughout Suffolk and Nassau counties, hitting Carvels, Dunkin’ Donuts and Subway shops.

“They’re very brazen,” one woman told CBS2’s Raegan Medgie.

“I think it’s terrible,” another man added. 

So far, the suspect has robbed four places in Suffolk County, seven in Nassau County, plus one attempt, Medgie reported.

“If they get away with it once, twice, they keep going until either they get caught or they feel that they’re at the limit and they just go somewhere else,” the woman said.

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“If it was the same person, police need to step up their game a little bit, I guess,” a man added.

The crimes date back to February 13.

“In all of the robberies, the suspect displayed either a machete or a large knife. He demands money,” Suffolk County Police Commissioner Tim Sini said. “He’s worn a dark colored knit wool hat, a dark jacket, or a sweatshirt.”

“As far as frustration goes, we try to solve every one, and we would like nothing better than to have a successful conclusion to this investigation,” Det. Sgt. James Madden said.

Suffolk County police announced a $5,000 reward for information leading to an arrest, WCBS 880’s Myles Miller reported.

Police say no one has been hurt in the robberies, and they’re asking store clerks to stay alert and not fight back.

In the most recent robbery, Game Stop officials say they are working with police to try and help catch the suspect.

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The investigation is ongoing.