Fire started by careless crooks.
This fire was started by some young men who were attempting to steal gasoline from the truck. One of the men dropped a cigarette. The fire blossomed and flashed over the entire structure in less than 5 minutes. They left their equipment in their hurry to get out.
The exposed foam intensified the heat to thousands of degrees F in just a few seconds. Note: the urethane on the door kept the fire from destroying the door.