Firefighters scrambled to extinguish a fire in a South Seattle residential building early Wednesday. Crews responded to the scene, a large home in the 6200 block of 46th Avenue South, at about 4:30 a.m. after receiving reports of smoke and flames spewing from the structure. After the blaze was extinguished, firefighters searched through the building but found no one inside. No injuries were reported. Crews ventilated the building before returning to service. The cause of the fire is under investigation.