It happened around 2:10 a.m. Wednesday at the BP gas station located at 7554 City Avenue in Philadelphia's Overbrook Park section.
Initial reports are that at least one suspect was armed with a handgun. A clerk there suffered an injury to the head but what is not clear is if the men made off with anything.
Police employed the assistance of a K9 unit in the hope of getting a scent on the suspects.
The investigation is ongoing.