Several of Mayor Zohran Mamdani’s progressive allies were arrested on Thursday blocking First Avenue hours before Israeli Prime Minister Benjamin Netanyahu’s combative address to the U.N.

Darializa Avila Chevalier — who won a Democratic congressional primary earlier this year highlighting her opposition to Israel’s war in Gaza — City Councilmember Chi Ossé, Assemblymember Emily Gallagher, and Gustavo Gordillo, the co-chair of the Democratic Socialist of America's New York City chapter, joined several dozen protesters blocking the street and carrying “End the Genocide” banners.

“You cannot enact a genocide and walk freely through the streets of New York,” Avila Chevalier told reporters as police assembled around the protesters. “There has to be accountability.”

The protest organized by Jewish Voice for Peace drew hundreds of people to the intersection of 39th Street and First Avenue, just a few blocks south of U.N. headquarters. Activists sat in the street blocking traffic as yellow taxis and black cars with diplomatic plates backed up and honked their horns.

Police officials said more than 100 people were taken into custody. Others arrested included the actress Susan Sarandon, actor and comedian Caleb Hearon, and former Army intelligence officer and whistleblower Chelsea Manning.

Mamdani, who as a candidate vowed to arrest the Israeli prime minister for war crimes, has repeatedly called Netanyahu a war criminal and the “architect of a horrific genocide against Palestinians.” But ahead of Netanyahu’s first visit to New York since Mamdani was sworn in as mayor in January, Mamdani said he would not join protesters on the street while emphasizing he would uphold New Yorkers’ right to demonstrate peacefully.

Just before Netanyahu took the stage before the U.N. General Assembly, Mamdani released a video showing him dining at Gracie Mansion with Palestinian families from Gaza and planting an olive tree — a universal symbol of peace, and of Palestinian pride and resilience.

In his speech, Netanyahu pushed back on criticisms that Israel has committed a genocide against Palestinians, and blamed Mamdani for making Jewish New Yorkers feel less safe.

Referring to Mamdani’s threats to arrest him, Netanyahu said, “Mr. Mamdani, you try to stop me from coming here. You try to silence me.”

At one point, Netanyahu invoked the social media activity of Mamdani’s wife Rama Duwaji, an artist who is of Syrian descent. According to the Free Beacon, as a teenager she once shared a post saying Tel Aviv “shouldn’t exist in the first place.”

Duwaji has kept a low profile as first lady. Mamdani has said his wife is a “private person.”

Public opinion has shifted sharply away from Netanyahu in the nearly three years since he unleashed a war in Gaza following Hamas' Oct. 7, 2023 attack on Israel.

In 2024, the International Criminal Court issued arrest warrants for Netanyahu and his former Defense Minister Yoav Gallant, accusing them of war crimes and crimes against humanity in Gaza.

B’Tselem, a leading Israeli human rights monitor, and Physicians for Human Rights-Israel, have both said that Israel is committing a genocide in Gaza. They join Human Rights Watch, Amnesty International, and the International Association of Genocide Scholars in making that determination.

The war in Gaza has killed over 70,000 Palestinians, including 20,000 children, according to an independent U.N. commission report published in June.

"As he has done time and again, Prime Minister Netanyahu used his speech to repeat baseless lies meant to sanitize his genocide of Palestinians," Mamdani said in a statement following Netanyahu's speech to the U.N. "Yet no lie can change the fact that he remains the subject of an International Criminal Court arrest warrant alleging war crimes and crimes against humanity.”

Several blocks west of the protest, posters with Netanyahu's face appeared with the words "Wanted for Genocide."

Brad Lander, the former city comptroller who won a Democratic congressional primary this year with Mamdani’s backing, attended the protest but moved aside when police started ordering people to clear the roadway. Lander told Gothamist he had a conflict later in the afternoon and didn’t plan to engage in civil disobedience.

" You try to figure out at each moment what's the best way you can contribute," he said.

Sumaya Awad, director of strategy at the Adalah Justice Project, a pro-Palestinian advocacy group, said it didn’t bother her that Mamdani hadn’t joined protesters in the streets.

“The question for me is, is he doing everything in his power, in his role, to push for the arrest of Netanyahu,” she said. “And I think he is doing that in really extraordinary ways that I haven’t ever seen before in New York City.”

Pro-Palestinian protesters are expected to gather later on Thursday to march from Bryant Park to the U.N. headquarters. On Wednesday, some of New York's largest Jewish organizations joined together for a rally against antisemitism.

Gustave Kerndt, a 25-year-old activist who traveled to New York City from Washington, D.C., to protest Netanyahu's speech, was visibly moved as Avila Chevalier — who is widely expected to win her congressional race after clinching the Democratic nomination — was handcuffed and led onto a police bus.

" It just shows how far we've come. I would've never guessed that members of Congress would be sitting in opposition to Benjamin Netanyahu coming to the United Nations," he said. "They're going to need bigger and bigger buses every single time a war criminal shows up in the United States."