Heart-wrenching photos mark the 70th anniversary of the liberation of Auschwitz

Tuesday is International Holocaust Remembrance Day, marking the passage of 70 years since the Jan. 27, 1945, liberation of the Auschwitz-Birkenau concentration camps built and operated in occupied Poland by Nazi Germany. As many as 1.1 million people, mostly Jews from across Europe, were killed there in gas chambers or by systematic starvation, forced labor and disease.

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