Authorities are investigating the Friday robbery of a bank in Valley Stream, Nassau County police said.

No injuries were reported, and there were no customers in the bank at the time of the robbery, police said.

According to detectives, a man entered Roslyn Savings Bank on North Central Avenue about 3:30 p.m., displayed a handgun and forced an unarmed security guard to the floor.

Police said the robber then ordered two other employees to the floor and demanded cash from a third before running away.

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The suspect is in his mid-20s, 5-foot-7 to 5-foot-10, with a thin build, police said.

Detectives asks anyone with information about the robbery to call Crime Stoppers at 800-244-TIPS. All callers will remain anonymous.