The Bernie Sanders campaign has suspended its Jewish outreach coordinator, Simone Zimmerman, just two days after hiring her, the New York Times reported Thursday.

The suspension came hours before the Democratic presidential debate in New York and after it was revealed that Zimmerman had previously criticized Israeli Prime Minister Benjamin Netanyahu on Facebook. “She has been suspended while we investigate the matter,” Sanders spokesman Michael Briggs told the New York Times.

When Zimmerman was appointed Tuesday, much of the American Jewish establishment vehemently condemned her for her record of criticizing Israel’s policies in the West Bank and Gaza. Zimmerman has been involved in left-wing activism around the Israeli-Palestinian conflict for years, supporting positions such as the Boycott, Divestment and Sanctions movement against Israel that mainstream Jewish organizations strongly oppose. She also founded a group of young American Jews called IfNotNow that wants to end Israel’s occupation and has written positively about Jewish Voice for Peace, another progressive group that seeks to end the Israeli occupation and says it supports "self-determination for Israelis and Palestinians" but that the Anti-Defamation League lists among its top-10 anti-Israel groups.

But a fresh wave of anger came after a report on Wednesday from the conservative Washington Free Beacon that found an old Facebook post in which Zimmerman used profanity directed at Netanyahu. “Bibi Netanyahu is an arrogant, deceptive, cynical, manipulative ass____. He is the embodiment of the ugliest national hubris and tone-deafness towards the international community,” Zimmerman wrote in the March 3, 2015, post.  “F--- you, Bibi.”

In the post, Zimmerman also wrote that Netanyahu “sanctioned the murder of over 2,000 people this summer,” referring to the Israel-Gaza conflict of 2014.

Former Anti-Defamation League head Abe Foxman called earlier Thursday for the Sanders campaign to fire Zimmerman, and Ronald Lauder, president of the World Jewish Congress, issued a statement asking the Sanders campaign to end its relationship with the activist.

“We are known by the company we keep, and those whose advice we seek. Bernie Sanders’ hiring of Simone Zimmerman as his chief adviser on Jewish issues is cause for profound concern,” Lauder’s statement said. “I call on Senator Sanders to clarify his own positions and whether this hire reflects his views on Israel. Does he support the positions Ms. Zimmerman espouses? If not, he should make that clear by terminating her immediately as one of his closest advisers. If Senator Sanders maintains her as his adviser, it will confirm that his views on Israel match hers.”

For their part, Sander’s staffers and supporters were excited about the choice of Zimmerman when she was hired. Many tweeted their support to her as she received criticism for her views on Israel.

This controversy illuminates one of the divides between the Sanders campaign and that of his rival, Hillary Clinton. Sanders has consistently performed much better than Clinton among young voters, and Zimmerman’s views are shared by many millennials — including young Jews. The American Zionist movement has been struggling to adapt to social justice-focused young people in recent years, and Israel and the BDS campaign have become a heated topic on many college campuses.

Sanders has called for a more “balanced” approach on Israeli-Palestinian relations and said recently on CNN that Israel’s response in the 2014 Gaza war was “disproportionate.” Clinton, on the other hand, has largely stuck to the party line of strongly supporting Israel, without criticism.

Amid the controversy with the Sanders’ campaign, a new NBC/Wall Street Journal/Marist poll of New York primary voters on Thursday found that Jewish Democrats favored Clinton over Sanders, with 65 percent supporting the former secretary of state and just 32 percent going for Sanders, the first Jewish candidate to mount a serious campaign for the presidency.