B-Shift and call back firefighters arrived to find heavy smoke showing from a 1 story house. Crews from Engine 1 pulled a line and encountered heavy smoke and heat but quickly located the fully involved bedroom and brought the fire under control in about 5 minutes. Other units on scene went to work doing horizontal ventilation and checking for exposure. Units were on scene for about 2 hours doing overhaul and picking up. The fire was started from unattended children playing with a lighter. Everyone made it out without any injuries. Units on the assignment were Engine 1, 2, 6, Ladder 1, Rescue 1, and Unit 202.