Both incidents occurred on Friday, May 12.
Suffolk County police reported that at 9:42 a.m., a man between the ages of 25 and 30 attempted to rob the East Farmingdale Bethpage Federal Credit Union, located at 1033 Route 109.
The would-be robber allegedly passed a note to a bank teller demanding money, but the teller did not comply and the man fled on foot.
However, about 20 minutes later, the man entered a Melville Bethpage Federal Credit Union, located just over six miles away at 501 Walt Whitman Road.
At the Melville location, the suspect again passed a note demanding cash to a teller, who this time complied.
He fled on foot with the cash. The amount taken has not been released.
Police described the robber as a Black man who is approximately six feet tall with a thin build.
He was wearing a black hooded sweatshirt and maroon pants.
Detectives urge anyone with information related to the incident to contact the Major Case Unit at 631-852-6555.
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