High-tech Archaeologists Uncover Bones, Gas Chambers in Treblinka

Nazi camp was bulldozed in 1943 and excavation was barred after war out of respect for victims - but research team found largely 'non-invasive' route to examine remains, evidence.

The Nazis left no evidence behind at the Treblinka. After gassing an estimated 900,000 Jews and an unknown number of Roma in the camp in eastern Poland, Germany bulldozed it in 1943 and even planted crops and built a farmhouse on the leveled site. What was known about Treblinka came from the testimony of survivors who'd passed through it and that of captured guards.