 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 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.