This was the handiwork of Monsignor Hugh O'Flaherty, whose underground effort hid both Jews and Allied military from the Nazis during their occupation of Rome.
There is a fine TV movie, "The Scarlet and the Black," about O'Flaherty and how he ran rings around the Gestapo. Gregory Peck plays O'Flaherty, and Christopher Plummer plays Gestapo boss Herbert Kapler.