Yad Vashem lists 20 Bulgarians among its "Righteous Among the Nations" - individuals who acted to protect Jews from the Holocaust.

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Let us also tell our children about the Righteous Among the Nations.

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Indeed, the Polish constitute the largest group of the Righteous Among the Nations, the honorary title granted to all non-Jews who saved Jewish lives by Yad Vashem, the organisation charged with commemorating the Holocaust.

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Mr Obama later visited the Yad Vashem Holocaust memorial, which he said illustrated the depravity to which man could sink but also served as a reminder of the "righteous among nations who refused to be bystanders".

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