During WW2, British psychological warriors concocted and planted very numerous false rumors (around 6 new ones every day in 1941 !!) in order to sow discord among the Germans and also with the inhabitants of the German-occupied countries. Given that from 1938 onwards, British authorities had intensively cultivated anxiety about chemical attacks among the civilian population (with gas-mask drills in gas chambers, etc.), it was only a matter of time before some British psychological warriors concocted and planted an atrocity story of Nazi killings in gas chambers. All good rumors fly on fear after all.
Sibs
British Air Raid Precautions (A.R.P.) and chemical warfare
"Holocaust deniers are very slick people. They justify everything they say with facts and figures."