Though many Nazis were punished for the crimes they committed during war time, not all war criminals of World War II suffered consequences for their actions. In fact, the video below details a long list of war crimes history has largely forgotten: Japanese army Unit-731.
Officially known as a "research and development unit," Unit-731 took its "research" to inhumane extremes attempts to study the human body and how weaponry affected it.
What on the surface portrayed itself as a water purification department actually partook in nefarious and gruesome human experiments that took the lives of 3,000 people - men, women, children, and even infants.
Despite the numerous horrors known to be committed by Unit-731, it never received any punitive actions for its crimes against humanity. Watch the video below to learn just how depraved they were, and how it helped them get away with it.