BOONE, Iowa—The Boone Fire Department was called about 1:00 Sunday afternoon to the Agri-Pak/APC building on the east side of Boone Sunday afternoon with a report of smoke coming from the building. Officials report that black smoke was coming from the building when fire fighters arrived at the scene. Because of the size of the building, multiple departments were called for help along with Boone County Search and Rescue, Emergency Management and both the Boone Police and Boone County Sheriff’s Departments. The source of the fire was determined to be a large roll-off dumpster inside the building. Officials report that the fire had spread to some insulation on the wall, but they were able to quickly contain the blaze. Damage was limited to the immediate area of the fire, but there was substantial smoke in the building which required quite a bit of time for ventilation. Fire fighters also returned Sunday evening about 10:30 to deal with an apparent hot spot in the insulation. There has been no estimate of damages at this time and the exact cause of the fire remains under investigation.