The man walked into the Bank of America on Post Avenue in Westbury Friday afternoon.
He then jumped over the counter, gun in hand, demanded money, and claimed he had a bomb.
The teller handed over an undisclosed amount of cash and he took off.
No one inside the bank was hurt.
Detectives ask anyone with information regarding this crime to contact Nassau County Crime Stoppers at 1-800-244-TIPS.
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