 The Argentine Army detachment that protected neutrality along the border with Paraguay and Bolivia during the Chaco War used the Madsen in combat operations at least once in 1933 in the course of an engagement on the southern bank of the Pilcomayo river against members of the Maká tribe commanded by deserters who had looted a farm in Argentine soil, killing some of its inhabitants.When Brazil acquired some 23 CV-35 tankettes from Italy in the late 1930s, it armed a majority of the vehicles with twin-mounted 7 mm Madsens.It was standard equipment (in 6.5 mm) with the Royal Netherlands East Indies Army (KNIL) during the inter-war period until 1942.