MEDICAL LAKE, Wash. - Fire crews are trying to figure out what caused a fire Monday morning in Medical Lake. It broke out at about 1:00 p.m. on Bartholomew Road. Firefighters tell us a trailer caught fire, eventually causing the roof to collapse. The building was used as a dog kennel and storage shed. As of 4:00 a.m., investigators were still on the scene looking for hot spots. About 35 firefighters were called to the blaze. No one was hurt or evacuated. The dogs that were in the kennel are all safe.