After the arrest of Mussolini on July 1943 and the launch of the long Anglo-American invasion of Italy, from the south, during 1944 Vittorelli made his way to Italy and joined the recently launched anti-monarchist anti-fascist Action Party. He accepted appointment as editor-in-chief of the Piedmont edition of the party's clandestine newspaper "L'Italia Libera", following editor Ginzburg's arrest and death by torture.