The Italian resistance movement became increasingly active in the German-occupied zone. Levi and some comrades took to the foothills of the Alps, and in October formed a partisan group in the hope of being affiliated to the liberal "Giustizia e Libertà". Untrained for such a venture, he and his companions were arrested by the Fascist militia on 13 December 1943. When told he would be shot as an Italian partisan, Levi confessed to being Jewish. He was sent to the internment camp at Fossoli near Modena. He recalled that as long as Fossoli was under the control of the Italian Social Republic, rather than Nazi Germany, he was not harmed.