Between September 1939 - July 1942 150,000 Jewish refugees arrived in Warsaw, most of them from Poland and some from the Reich.
The German Jews in Warsaw were among the first Jews to be sent to their deaths in the Treblinka death camp in July 1942.
http://www1.yadvashem.org/exhibitions/Katz/katz_home.htm

Archival Footage courtesy of Bundesarchiv-Filmarchiv & Transit Film