In 1940, she built an indoor Sports arena, which cost over 250,000 reichsmarks (approximately $62,500), most of which had been seized from the inmates. In 1941 Karl Otto Koch was transferred to Lublin, where he helped establish the Majdanek concentration and extermination camp. Ilse Koch remained at Buchenwald until 24 August 1943, when she and her husband were arrested on the orders of Josias von Waldeck-Pyrmont, SS and Police Leader for Weimar, who had supervisory authority over Buchenwald. The charges against the Kochs comprised private enrichment, embezzlement, and the murder of prisoners to prevent them from giving testimony.