"The attached photo from the 6 April 1945 issue of 'The Railway Gazette’ shows a US Army captured German StuG Assault Gun that an MRS unit converted to serve as a shunting (switching) locomotive to move railway cars over covered tracks laid on city and dockyard streets and within warehouses or other covered storage areas. The reason the conversion was made either because the warehouses, dockyard or storage areas were subject to a fire hazard if a steam locomotive was used or because the track curvature was too sharp or too light to enable use of a standard Army steam shunting (switch) locomotives or one of the available French or Belgium locomotives. The backdrop of the photo shows what appear to be a merchant ship crane boom so this photo may have been taken at a harbor dock. 

The StuG would have been operated by one of the unit’s locomotive engineers who would be guided by hand signals given by an Army brakeman or switch crew. The conversion was likely made by one of the US Army Railway Operating Battalions or one of the attached US Railway Shop Battalions. The StuG apparently is equipped with a rigid welded steel bracket at each end to enable it to couple to the railway car but it is not equipped with any type of freight car buffers. It cannot operate the railway cars brakes and would depend on its weight and tracks to slow and stop the cars. 

The Railway Gazette was a British magazine that discussed the British railway industry and railways world wide. 

Thanks Richard

Ling to Journal page HERE