On May 13, 1943, German military doctors allowed Allied prisoners of war to observe the autopsies of victims killed by Soviet forces in the Katyn Forest, as part of the International Katyn Investigation. On the left is the German forensic scientist who chaired the Katyn massacre investigation. On March 5, 1940, Soviet authorities decided to execute more than 21,000 Polish nationals who had been taken prisoner after the Soviet invasion of Poland. The executions were carried out by the NKVD, the Soviet political police.
After the discovery of the mass graves in the Katyn Forest was announced on April 11, 1943, Lieutenant Colonel Van Fleet Jr. was selected, along with Lieutenant Colonel Stuart and Lieutenant Colonel Frank Parker Stephenson, at Oflag IX/AZ to participate in the International Katyn Commission's exhumation work in the Katyn Forest. On May 13, 1943, Allied prisoners of war participated in the activities of the International Katyn Commission, viewing many exhibits and witnessing the autopsies.
It was determined that the massacre in the Katyn Forest included more than 25,000 Poles. The breakdown was 8,000 officers, 6,000 police officers, and 8,000 civilians, including priests, rabbis, nobles, and professionals. Additionally, 14 generals, 1 admiral, 24 colonels, 79 lieutenant colonels, 17 naval captains, 3,000 non-commissioned officers, civilians, civil servants, intellectuals, and 200 pilots—including Janina Lewandowska, the first female pilot in the Polish Army—were also among the victims.














