Germany and Italy were allies until September 1943. After Italy agreed to a ceasefire with the Western Allies, Germany occupied the country and deported some 600,00 members of the Italian armed forces. As so-called "military internees," they were not subject to the same legal protections that applied to prisoners of war.
Site of the Shooting of "Italian Military Internees"
Here, members of the SS shot seven "Italian military internees" in front of 50 other Italian inmates.