Ben Franklin Fire House, 4th & Arch, 12:58 pm by JONATHAN VALANIA

RELATED: A fire erupted at a firehouse in downtown Philadelphia Friday causing extensive damage. The fire started at about 11:30 a.m. at the firehouse located at 4th and Arch Streets in Old City. In a twist of irony, firefighters had to turn their water hoses on their own building and attempt to contain the fire. It took firefighters approximately 15 minutes to bring the blaze fully under control, but not before the fire caused severe damage to the firehouse. The flames were so intense that at one point, several of the firehouse’s doors melted. It appears preliminary that the fire started in a medical unit ambulance that was parked inside the firehouse. A second medic unit vehicle was damaged. The engine of the medic unit exploded, sending flames and smoke through the ceiling and into the overhead doors. MORE