The anti-Defamation League and the National Jewish Democratic Council on Monday condemned Breitbart News for featuring an article titled, “Bill Kristol: Republican Spoiler, Renegade Jew.”

In an article posted Sunday night on Breitbart’s home page, author David Horowitz suggested that Kristol was betraying his fellow Jews for opposing Donald Trump’s candidacy and seeking a third-party candidate to run for president in the fall. Horowitz, who’s Jewish, wrote the following: “I am a Jew who has never been to Israel and has never been a Zionist in the sense of believing that Jews can rid themselves of Jew hatred by having their own nation state. But half of world Jewry now lives in Israel, and the enemies whom Obama and Hillary have empowered — Iran, the Muslim Brotherhood, Hezbollah, ISIS, and Hamas — have openly sworn to exterminate the Jews. I am also an American (and an American first), whose country is threatened with destruction by the same enemies. To weaken the only party that stands between the Jews and their annihilation, and between America and the forces intent on destroying her, is a political miscalculation so great and a betrayal so profound as to not be easily forgiven.”

The Twitterverse immediatly erupted in outrage.

“We are disappointed that @BreitbartNews invoked Bill Kristol’s religion in #RenegadeJew headline. So inappropriate and offensive,” The ADL tweeted on its main Twitter account on Monday.

“While we disagree deeply with Bill Kristol on many issues, there is no question that Breitbart’s attack on Mr. Kristol as a ‘Renegade Jew’ is completely unacceptable,” the NJDC said in a statement. “The author of the piece, David Horowitz, specifically chose to include ‘Renegade Jew’ in the post’s headline and should know better. We share the widespread and growing disappointment – including by the Anti-Defamation League – in Breitbart’s inappropriate and offensive headline and we believe that more must be done. Mr. Horowitz must apologize immediately and help ensure that these sort of attacks must not be allowed to become the new normal. Andrew Breitbart, z”l, would have been deeply ashamed.”

Horowitz told the Daily Caller in an email that he is responsible for the headline “Renegade Jew.” He later doubled down on his claim in another post on Breitbart News.