Police responded to a report of a robbery at the A to Z Store on the 100 block of Weidman Street in Lebanon around 6 p.m. Monday night.
Officials say a male entered the store, displayed what appeared to be a handgun and demanded money from the clerk.
The clerk says the suspect was wearing a hood cinched tightly over his face and that the suspect slammed the gun on the counter and fired it.
When the gun went off, the clerk determined it was not a real gun but an airsoft type gun that fired plastic pellets.
The suspect got away with an undetermined amount of money, according to officials.
Police say the suspect is described as a male in his late teens, early twenties, with blonde hair. He was seen wearing an olive green camouflage hooded jacket.
Anyone with information is asked to contact the Lebanon City Police Department.