Investigators believe a house fire at N. 6th Avenue was set intentionally. Firefighters are investigating a suspicious house fire at the 600 block of N. 6th Avenue. Crews with the Yakima Fire Department (YFD) responded and found flames at the outside of the home spreading to the alley, around 2:15 p.m., Tuesday. The blaze also caused nearby electrical power lines to spark. Firefighters said people live at the home, but no one was inside at the time the fire started. YFD officials say the cause of the fire appears to be suspicious and continue to investigate.