Hundreds of thousands of protesters gathered around Hostages Square in Tel Aviv on Sunday night, with organizers reporting a turnout exceeding 400,000. In one of the largest coordinated demonstrations since the beginning of theGaza warnearly two years ago, protesters blocked major roads, closed private businesses, and staged rallies in big cities across Israel. Thenationwide grassroots strikeand widespread protests grew over the course of Sunday as protesters demand the government secure the release of 50 hostages still in Gaza. People also protested outside government ministers' homes. The day of protests began at 06:29 a.m., the exact time when Hamas launched its deadly attack on Israel on October 7, 2023. Organizers said that throughout the day, over one million people participated in hundreds of actions held across the country. At the start of the main rally at Hostages Square, a new video clip of the captive Matan Zangauker was released. The video, said to be recorded several months ago in Gaza, was recently obtained by the Israeli military during its operations and was released by Einav Zangauker, Matan's mother, as part of the intensifying campaign to free the hostages. In the video, Zangauker appears with a shaved head and addresses his sisters and his partner, who was kidnapped with him from Kibbutz Nir Oz and was released after 50 days in November 2023. In the video, Zangauker appears, saying: "Tatu (Natali), Shani, Ilana – I miss you, and God willing, we'll meet soon. To all my acquaintances, all my friends – go out and make noise like only you know how." After the video was released, Einav Zangauker spoke at the Hostages' Square and said: "Your quiet gaze at the end of the video accompanies me as I toss and turn in bed at night. My soul burns with longing; it burns that I cannot hug you, hear you, and hold you." In her speech, Zangauker criticized the government's conduct. "They have turned the most just war into a futile war. If Netanyahu wants an agreement, let him put a comprehensive proposal on the table and agree to it; otherwise, he is simply lying," Zangauker added. Family members of the hostages, leading the strike alongside the October Council, which represents bereaved families from the war, held a press conference in Tel Aviv, announcing an "emergency break" until the hostages are released. "Today, we stop everything to save the lives of 50 hostages and soldiers. Today, we stop everything to remember the supreme value of the sanctity of life," said Anat Engrest, whose son Matan is held in Gaza. Polls have repeatedly shown a large majority in Israel support a ceasefire deal to release all of the hostages in exchange for an end to the war. The last round of negotiations fell apart in late-July, when the US and Israelwithdrew their teamsfrom talks in Doha, accusing Hamas of not negotiating in good faith. "We are united in one simple demand directed at the Israeli government: Put an Israeli proposal on the table today for a comprehensive deal – to end the war in exchange for the return of the last hostage. No slogans, no sabotage, no demands that we know the other side won't accept," said Vicky Cohen, whose son Nimrod is a hostage. "It's time to end the horrific nightmare the entire country has been living in for 22 months." The strike was announced last week, following the Israeli security cabinet's decision to expand the war andtake over Gaza City, despite the Israeli military's warning that the operations could endanger the 50 remaining hostages in Gaza, 20 of whom are believed to still be alive. The Israeli military says the operation will begin "soon" and the government says it will provide the local population in Gaza with tents before relocating them "for their protection." Almost the entire population in Gaza has been displaced, with many forced to move multiple times. As of early Sunday afternoon, Israeli police say 38 protesters had been arrested across the country for disturbing the peace. Israel's largest labor organization, the Histadrut, did not join the strike, though it encouraged employers to let workers participate. But many technology companies, law firms, academic institutions and private sector enterprises announced their participation and support, alongside citizens who declared they would take the day off or refrain from business transactions. Israeli President Isaac Herzog expressed support for the hostage families, while visiting the central gathering at Hostages Square. "All of the people of Israel are anxious, concerned, and want the hostages to come home. There is not a single Israeli woman or man who does not want them home," Herzog said. But members of the Israeli government slammed the day of protests. Prime Minister Benjamin Netanyahu told a cabinet meeting: "Those who are calling today to end the war without defeating Hamas not only harden Hamas's stance and delay the release of our hostages – they are also ensuring that the horrors of October 7 will repeat themselves again and again." Itamar Ben Gvir, the far-right Minister of National Security, said the strike was a "cynical political maneuver on the backs of the hostages," linking it to long-standing anti-government protest movement. The Hostages and Missing Families Forum, which represents most of the hostages who remain in Gaza, said in response: "You can continue to hide behind spins and political calculations, but you cannot escape responsibility." The Forum announced plans to set up a protest encampment on the Gaza border called "Waypoint 50" – representing the 50 hostages – to continue pressuring the government to secure their release. For more CNN news and newsletters create an account atCNN.com