Engine 34 with Chief 3C (OIC), Chief 3A, Chief Engineer, Past Chief B. Shea, Command 3 with Chief 3, AR. Wallmark and A37 with EMS LT and Past Chief C. Franklin responded mutal aid to St. Mary's Co. to 45915 Patuxent Lane, California, MD for the working house fire with entrapment. Engine 34 and Command 3 arrived on the scene with Engine 291 of a 2 story single family dwelling fully involved. The order was given by Command Chief 23 for exterior operations only. Engine 34 relayed water supply to E291 and the crew assisting with the fire attack. Chief 3 was given division A then Operations. Chief 3A was given Divison C then Safety. A37 assisted Co. 38 with rehab. Fire was placed under control by command with no entrapment. State Fire Marshal's Office is investigating the fire.