Elhame Hassan Basyouny, a 21-year-old, was taken into custody and charged with terroristic threats, the department said.
It all happened at the Wells Fargo at 1901 South 4th Street, the department wrote in a release. A customer was leaving the bank just after 4 p.m. when he "stated there was a bomb inside," according to investigators.
Firefighters helped evacuate the building before police K9 units swept the scene, authorities said. No bombs or explosive devices were found.
Court records show Basyouny was arraigned early on Tuesday, Aug. 1 and his bail was set at $25,000.
The matter remains under investigation by Allentown police and the FBI.
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