Deputies were called out to the Arco off Highway 99 at Road 122-B in Pixley just after 1 a.m.
They learned that three masked men had demanded money from the cashier.
Two of the suspects were armed with bats and pipes. The third man had a gun.
After getting some cash, the men drove off in a burgundy-colored four-door car.
Anyone with information on this case is asked to contact the Tulare County Sheriff's Office.