Just before 4 AM this morning, crews were alerted to Circle Ave. for the house on fire. Engine 73 quickly responded with 4 volunteers and arrived on the scene to find a 1 story duplex with fire throughout. The crew stretched an attack line and began to attack the fire. Other arriving crews found that the fire had also extended into the attached residence. Units from multiple departments worked together to contain the fire. Units remain on the scene and will for several more hours assisting the Fire Marshal. Thanks to Alexandria Engine 201 for filling our station.