Investigators are trying to figure out exactly what sparked an overnight fire at a chicken feed factory in Tacoma. The blaze broke out late Monday night at a building in a commercial area near the intersection of St. Paul Avenue and Portland Avenue East. Investigators say the fire appears to have started in some equipment at the scene. Flames then spread to insulation in the roof. An employee at the factory noticed the smoke and called 911. Firefighters responded and doused the blaze. There were no reports of any injuries.