Archaeologists working in Lithuania have uncovered a tunnel Jewish prisoners used to escape Nazi captivity during Lithuania’s infamous Ponary massacre. Using noninvasive technology, they located the long-lost route in the Ponar forest just outside the Lithuanian capital of Vilnius, according to The New York Times.

Historians estimate that 100,000 people in the region were killed by Nazis between 1941 and 1944, and their bodies were dumped in mass graves. The death toll included 70,000 Jews from the city that Napoleon famously called the Jerusalem of the North. In 1943, as the Germans were retreating from oncoming Soviet forces, the Nazis began trying to cover up the evidence of the genocide, forcing 80 prisoners from the Stutthof concentration camp to dig up and burn the bodies. At night, the prisoners were chained together in a deep holding pit (seen above) previously used for executions.

Using their bare hands and spoons they found on the bodies they were burning, the prisoners spent three months digging an approximately 100-foot-long tunnel out of the pit. In April 1944, about 40 of the prisoners cut their shackles with a nail file and crawled through the tunnel toward freedom. But guards caught wind of the escape in progress, and only 11 prisoners made it out of the camp alive and through the forest to Allied forces to survive the war.

A team of researchers from the Israel Antiquities Authority, the University of Hartford in Connecticut, Vilna Gaon State Jewish Museum, and the Canadian consulting firm Advisian used radar and a geophysical imaging technique called electric resistivity tomography to find locations where the soil looked like it had been disturbed, locating both the tunnel and a previously unknown execution pit.

The Ponar discoveries, as well as the researchers’ work rediscovering the archaeological site of the destroyed Great Synagogue of Vilnius, will be detailed in a NOVA documentary in 2017.

“The exciting and important discovery of the prisoners escape tunnel at Ponar is yet more proof negating the lies of the Holocaust deniers,” Israeli culture minister Miri Regev said in a press statement. “The success of modern technological developments, that have aided the Jewish people to reveal another heroic story the Nazis attempted to hide, profits all humanity.”

[h/t The New York Times]

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