The firing prompted Mike Huckabee and Sarah Palin, among others, to call for NPR to be stripped of federal funding.
Ailes later semi-apologized for his comment in a letter to the Anti Defamation League.
"I was of course ad-libbing and should not have chosen that word, but I was angry at the time because of NPR's willingness to censor Juan Williams for not being liberal enough," he wrote, as TV Newser reports.
"I'm writing this just to let you know some background but also to apologize for using 'Nazi' when in my now considered opinion, 'nasty, inflexible bigot' would have worked better," he added.
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