1940: In Warthegau, Polish territory annexed by Germany in 1939, Herbert Lange’s Sonderkommando used a large van fitted with a sealed chamber to eliminate mental patients. To allay suspicion, the side of the vehicle carried the logo of a well-known German coffee company – “Kaiser’s Kaffee-Geschäft”. Once the patients were loaded, carbon monoxide was piped into the chamber.
Source: Patrick Montague, Chełmno and the Holocaust: The History of Hitler’s First Death Camp (2012), pp. 21–30, 64, 199–211