Yehiel De-Nur (Hebrew: ????? ??-????; De-Nur means 'of the fire' in Aramaic; also Romanized Dinoor, Di-Nur), also known by his pen name Ka-Tsetnik 135633, born Yehiel Feiner (16 May 1909 – 17 July 2001), was a Jewish writer and Holocaust survivor, whose books were inspired by his time as a prisoner in the Auschwitz concentration camp.
His work, written in Hebrew, tends to "blur the line between fantasy and actual events" and consists of "often lurid novel-memoirs, works that shock the reader with grotesque scenes of torture, perverse sexuality, and cannibalism".