Surveillance video of the Dairy Queen fire on 4/15/17 shows fire resulted from spontaneous combustion of laundered rags used for cooking oil clean up.
In the video, milk crates can be seen in the reflection of the chrome on the dryer door. At the 00:20 mark, ignition of the rags in the crate is seen and the fire progresses up the wall left of the camera. At 00:25, a flame is seen near the mop sink and is a reflection from the clear plastic dome of the surveillance camera, as there was no fire in this area. At 00:49, the surveillance camera begins to fall from the mount and angles down toward the fire.
