Large numbers of political dissidents, including Abwehr personnel, sought refuge in Portugal after the plot of 20 July 1944 to assassinate Adolf Hitler. Until late 1942, immigration was very restricted. In cases in which refugees were suspected to desire not simply to pass through Portugal in transit to their destination, but rather intended to remain in the country, the consulates needed to get a previous authorization from Lisbon. This was frequently the case with foreigners of indefinite or contested nationality, stateless individuals, Russians, and Jews expelled from their countries of origin.