Thursday morning at 0611hrs stations 1/27 were alerted to a commercial vehicle fire. Engine 1-6 was the first to arrive with smoke coming from the rear cargo compartment of a UPS tractor trailer. Crew members advanced an inch and three quarter line and quickly extinguished the fire. Crews from 27-5 and R27 assisted w/ salvage and overhaul. The scene was placed under control by Lt. 1 at 0647hrs. Units making the response were 1-6, R-27, and 27-5.