At 1339 hrs. Georgetown Fire Co Inc, Bridgeville Fire Co, Georgetown American Legion, & Sussex County Paramedics were dispatched for a working mobile home fire. 77 Command with Fire Chief Joey Pepper arrived on scene with nothing showing on side A. Chief Pepper did a walk around of all 4 sides of the structure with still nothing evident from the exterior. However, further investigation found that the interior of the residence was full of black smoke and a working fire was in the side A & D in a rear bedroom. Eng. 77-4 responded with F/F Craig Eaton as officer and they were assigned to back down the narrow lane, force entry, and to put the rear 200' 1 3/4" line in service through the front door side A. Tanker 77 with 1st Asst. Chief Penuel Barrett was assigned to nose up to Eng. 77-4 for supply and also handle interior operations. Tanker 77's crew assisted the first line, primary search, and ventilation. Eng. 77-1, with Past Chief Jim King as officer, staged on the lane, hooked into Tanker 77 and crews from 77-1 did secondary search and assisted with overhaul. Rescue 77, with F/F Ricky Hudson as officer, staged on the roadway. Rescue 77's crew set up PPV on side B door and refilled SCBA. Eng. 72-9 & Tanker 72-5, with Fire Chief Jack Cannon, was assigned R.I.T., relief crew, and some minor overhaul of the exterior of the residence. Sussex County Paramedic Medic 103 established rehab on side A front lawn and treated one of the home owners for a minor medical problem. Eng. 75-2 from Ellendale Fire Co. stood by at Station 77. Fire was contained to the the bedroom with minor smoke damage throughout the residence. Situation was placed under control at 1419 hrs. & turned over to the Delaware State Fire Marshals Office.