Nick,
I am researching this vehicle for some time and I think this was a German design, problably on Krupp truck chassis.
It might be related to the Wilton-Feyerenoord armoured car that was built on a Krupp chassis as well.
I have another pciture of the same vhicle (with a sister car). These two served with the Shanghai Police Dept.
Here's a link with some pictures to add to the discussion:
http://www.network54.com/Forum/threa...eid=1099248579
For the similar WF cars, see my chapter on foreign built armoured cars in
Overvalwagens!
Regards,
Nuyt