[Rolf S. Ask]

My guess is some sort of crash/rescue truck...
There seems to be a handle just under the window.
Pitty we do not see the runningboards. But it could be a shelter for someone standing on the running board rushing forward to assist some help in a hurry in a situation I can not imagine.

And notice how the door seems to be in a much better state than the rest of the truck. Can the door have been fittet later, or has it just been shelteres under the wings?

Rolf