For the second time in the past 30 days a knife-wielding robber held up a Baldwin Dairy Barn store, police said.

It is not known if the two robberies at the store on Grand Avenue are connected. The first one occurred April 29, and the second was Wednesday at 10:23 p.m., Nassau County police said.

Police said the robber, described as being in his late teens or early 20s, about 5-foot-9 or 5-foot-10 and with a slim build, possibly about 140 pounds, confronted the store employee, flashed a knife -- and stole cash and cigarettes.

The robber was wearing a zippered, black hooded sweatshirt, black sweatpants and black shoes, police said.

In the previous robbery, the suspect was described as being in his late teens, between 5-foot-8 and 5-foot-10 and about 150 pounds. Police said the suspect wore black sneakers, black cargo pants with zippered pockets, a black shirt, black baseball cap, black bandanna covering his face and a white belt with a diamond-shaped emblem. That robbery took place on a Sunday at about 12:30 p.m.

Police ask anyone with information about the robberies to call Crime Stoppers at 800-244-TIPS. All calls will remain confidential.

On the latest episode of "Sarra Sounds Off," Newsday's Gregg Sarra and Matt Lindsay take a look top boys and girls basketball players on Long Island. Credit: Newsday

Sarra Sounds Off, Ep. 15: LI's top basketball players On the latest episode of "Sarra Sounds Off," Newsday's Gregg Sarra and Matt Lindsay take a look top boys and girls basketball players on Long Island.

On the latest episode of "Sarra Sounds Off," Newsday's Gregg Sarra and Matt Lindsay take a look top boys and girls basketball players on Long Island. Credit: Newsday

Sarra Sounds Off, Ep. 15: LI's top basketball players On the latest episode of "Sarra Sounds Off," Newsday's Gregg Sarra and Matt Lindsay take a look top boys and girls basketball players on Long Island.

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