Jewish population of Silesia was subjected to Nazi genocide with executions performed by Einsatzgruppe z. B.V. led by Udo von Woyrsch and Einsatzgruppe I led by Bruno Streckenbach, imprisonment in ghettos and ethnic cleansing to the General Government. In their efforts to exterminate the Jews through murder and ethnic cleansing Nazi established in Silesia province the Auschwitz and Gross-Rosen camps. Expulsions were carried out openly and reported in the local press. Those sent to ghettos would from 1942 be expelled to concentration and work camps. Between 5 May and 17 June, 20,000 Silesian Jews were sent to Birkenau to gas chambers and during August 1942, 10,000 to 13,000 Silesian Jews were murdered by gassing at Auschwitz. Most Jews in Silesia were exterminated by the Nazis. After the war Silesia became a major centre for repatriation of the Jewish population in Poland which survived Nazi German extermination and in autumn 1945, 15,000 Jews were in Lower Silesia, mostly Polish Jews returned from territories now belonging to Soviet Union, rising in 1946 to seventy thousand as Jewish survivors from other regions in Poland were relocated. The majority of Germans fled or were expelled from the present-day Polish and Czech parts of Silesia during and after World War II. From June 1945 to January 1947, 1.77 million Germans were expelled from Lower Silesia, and 310,000 from Upper Silesia. Today, most German Silesians and their descendants live in the territory of the Federal Republic of Germany, many of them in the Ruhr area working as miners, like their ancestors in Silesia. To smooth their integration into West German society after 1945, they were placed into officially recognized organizations, like the Landsmannschaft Schlesien, with financing from the federal West German budget. One of its most notable but controversial spokesmen was the Christian Democratic Union politician Herbert Hupka. The expulsion of Germans led to widespread underpopulation. The population of the town of Głogów fell from 33,500 to 5,000, and from 1939 to 1966 the population of Wrocław fell by 25%. Attempts to repopulate Silesia proved unsuccessful in the 1940s and 1950s, and Silesia's population did not reach pre-war levels until the late 1970s. The Polish settlers who repopulated Silesia were partly from the former Polish Eastern Borderlands, which was annexed by the Soviet Union in 1939. Wrocław was partly repopulated with refugees from the formerly Polish city of Lwów. Cities The following gallery includes the cities