As the 2nd Infantry Division marched across Germany, it uncovered several sites of Nazi crimes. In early April 1945, the unit captured the German town of Hadamar, which housed a psychiatric clinic where almost 15,000 men, women, and children were killed between 1941 and March 1945 in the Nazi Euthanasia Program.

In the first phase of the killing operations (January to August 1941), Hadamar personnel murdered around 10,000 German patients by asphyxiating them with carbon monoxide in a gas chamber made to look like a shower room. From August 1942 to March 24, 1945, approximately 4,420 persons died at Hadamar.

Resident physicians and staff directly killed the majority of these victims, among whom were German patients with disabilities, mentally disoriented elderly persons from bombed-out areas, "half Jewish" children from welfare institutions, psychologically and physically disabled forced laborers and their children, German soldiers and foreign Waffen-SS soldiers deemed psychologically incurable. The medical personnel and staff at Hadamar killed almost all of these people by lethal drug overdoses and deliberate neglect.