Washington (CNN) A Florida Republican congressional hopeful who apparently called for Rep. Ilhan Omar and other Democrats to be hanged in a fundraising email has been removed from a GOP initiative that supports candidates.

George Buck Jr., who is challenging Democratic Rep. Charlie Crist in Florida's 13th Congressional District, threatens Omar and Reps. Ayanna Pressley of Massachusetts, Alexandria Ocasio-Cortez of New York and Rashida Tlaib of Michigan in an email obtained by CNN that was dated November 26 and includes his signature, though he has denied writing it. The email labels the four minority progressive lawmakers, who call themselves "The Squad," as "anti-American" and associates them with Crist.

"We should hang these traitors where they stand. I have no tolerance for those who are abusing our system to destroy our country," says the email, which also includes unsubstantiated allegations that Omar was a foreign agent. Buck has denied he wrote the email, saying, "I would never talk like that," the Tampa Bay Times reported . CNN has asked Buck to clarify his comment to the Tampa Bay Times.

Buck's campaign Facebook page on Wednesday posted three links to news stories about Omar, saying in one post , "How come no one is calling out Omar for her rhetoric?" Omar has drawn sharp criticism, including from some in her own party, for comments she's made about political support for Israel.

Asked for comment Wednesday, Buck said in an email to CNN: "I am a decorated veteran of the 101st Airborne Division. As someone who has taken the oath to defend the Constitution, I take that oath very seriously."

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