From 10 June 1940, when Fascist Italy declared war on Britain and France, the SDF was involved in the East African Campaign. At first, the SDF went on the defensive against attacks into the Sudan by forces of the Italian Royal Army (Regio Esercito) and the Italian Royal Air Force (Regia Aeronautica) based in Italian East Africa (Africa Orientale Italiana, or AOI). The Italians occupied the railway junction at Kassala, the small fort at Gallabat, and the villages of Ghezzan, Kurmuk, and Dumbode on the Blue Nile.