Among this year's 13 recipients of the Presidential Medal of Freedom, Mr. Obama posthumously honored Jan Karski.

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Jan Karski passed away more than a decade ago.

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Among them was Jan Karski, a young Polish Catholic, who witnessed Jews being put on cattle cars, who saw the killings, and who told the truth, all the way to President Roosevelt himself.

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And he announced he would award the Presidential Medal of Freedom, the nation's highest civilian honor, posthumously to Jan Karski, an officer in the Polish underground during World War II, who provided one of the first eyewitness accounts of the Holocaust.

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