TEL AVIV – Former adviser to Senator Bernie Sanders Simone Zimmerman was detained for questioning by the Shin Bet security agency at the border between Israel and Egypt for three hours on Sunday night.

In a tweet, Zimmerman said she and a friend, Abby, who the Haaretz daily identified as former Middle East peace Quartet employee Abigail Kirschenblum, claimed Israeli authorities had tried to intimidate her over her work with Palestinians.

“We’re out. That was four hours of rounds of interrogation, waiting and mostly attempted intimidation centering on our connections to Palestinians,” Zimmerman tweeted.

She claimed she was asked “Why did you come here to work with Palestinians? Why not with Jews?” as well as her opinion on Netanyahu.

“We are being questioned solely about our political opinions and activities vis a vis Palestinians esp in the occupied territories,” Zimmerman tweeted.

Zimmerman said she told the authorities that she is currently living in Israel and works for Gisha, an Israeli human rights organization that assists Gazans. Gisha is financed by the George Soros-financed New Israel Fund (NIF), a radical, foreign-funded anti-Israel NGO.

According to Zimmerman, the official stopped her and asked, “I want to know why you’re really here.”

“The scariest part is the horrifying realization of how badly the Israeli government wants to scare Jews away from Palestinians. They are using all tactics to make the cost of knowing & working with Palestinians too risky that we don’t dare to do it at all,” she tweeted.

Zimmerman was fired from her position with Democratic candidate Sanders in 2016 after it emerged that she had called Prime Minister Benjamin Netanyahu a “manipulative asshole” who is responsible for the mass murder of Palestinians.

“Bibi Netanyahu is an arrogant, deceptive, cynical, manipulative asshole,” she wrote in 2015. “Fuck you, Bibi… you sanctioned the murder of over 2,000 people this summer.”

During the 2014 Gaza war, Zimmerman was one of the leaders of a group of young Jews that held regular protest vigils outside the offices of the Conference of Presidents of Major American Jewish Organizations, reading the names of Palestinians and Israelis killed in the conflict.

Zimmerman opposes Israel’s policies in the West Bank, wants Hillel to allow participation by groups that support the Boycott, Divestment and Sanctions movement against Israel, is against Jewish federation funding for Israeli projects in the West Bank, and wrote favorably of the efforts of Jewish Voice for Peace, a pro-BDS group, to get “international corporations to stop profiting off human rights abuses.” (The Anti-Defamation League has called JVP one of America’s top 10 anti-Israel groups.)

Zimmerman is one of the founders of IfNotNow, which protests, among other things, Israel’s control of the West Bank, the Trump administration, and condemns American Jewish organizations that endorse them.

The group filmed walkouts of Birthright, with the claim that the Israel tour was “hiding the realities of the occupation.”