A Sd.Kfz. 251, an acronym for Sonderkraftfahrzeug 251, was a half-tracked, German-produced armored personnel carrier, which was in use on Earth during the 1930s-1940s by the German military, until the end of World War II.
The tube construction on top of the half-track, indicated that the vehicle was a command vehicle, equipped with extra radio equipment, or in German parlance a "mittlere Kommandopanzerwagen (Funkpanzerwagen)", and the third official variant, referred to by its ordnance number Sd.Kfz. 251/3. Considering that the next scene in "Storm Front", showed the Generalmajor still wearing his headgear and gloves, strongly suggested that he actually had arrived in the Sd.Kfz. 251, as a figure could be seen descending from the vehicle.
One of the more ubiquitous German military vehicles, it was also one which was not endowed "officially" with its own nickname, though it was often referred to by the name of its manufacturer, Hanomag, even though that name was also used for other types of German half-track vehicles. While several of these have survived the war, the scene was nevertheless entirely constructed as a CGI effect at Eden FX.