(NATIONAL POST) The Free Gaza Movement, a U.S.-based activist group known for provisioning ships to run the Israeli-Egyptian blockade of Gaza, was hit with charges of anti-Semitism on Wednesday after posting a tweet claiming that Jews were responsible for the Holocaust.

“Zionists operated the concentration camps and helped murder millions of innocent Jews,” read a Tweet posted Sunday to @freegazaorg, the official Twitter feed of the group, which includes Canadian author Naomi Klein and Bishop Desmond Tutu on its board of advisors.

An embedded link led to a video of a speech by known conspiracy theorist Eustace Mullins claiming that the word Nazi is an amalgam of the words “National socialism” and “Zionist.”

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