Thousands of people supporting Palestinian rights converged Saturday on Washington from around the country, demanding a cease-fire in the Gaza Strip and an end to American aid to Israel amid a deepening war.

Protesters filled in and flowed beyond Freedom Plaza, a block from the White House, with the crowd streaming for at least a half-mile down the surrounding streets. Anger and grief mixed with feelings of comfort and encouragement, attendees said, as people of all ages mingled with like-minded allies.

Similar rallies calling for a cease-fire unfolded Saturday in London, Berlin and elsewhere. The event in D.C., which concluded with a march through downtown streets to the White House, appeared to be one of the largest expressions of American solidarity with the Palestinian people to date. On the march, an 8-year-old boy carried a kid-sized red megaphone and led a chant: “Hey hey, ho, ho, the occupation has to go.” Arriving at the White House, a handful of people stood along the fence and waved Palestinian flags.

From the rally stage, speakers led the crowd in chants of “Free, free Palestine! Free, free Palestine!” and “Cease-fire now!” Many lashed out at President Biden for his support of Israel, which has responded to a Hamas attack on civilians with a deadly invasion of Gaza. Toddlers, teens and grandparents alike wore kaffiyehs, and strangers passing on the sidewalk made the “V” peace sign and said “free Palestine” to one another. A long row of faux coffins were on display, draped with Palestinian flags. As the event wound down, a group unfurled a long scroll of paper listing more than 8,000 names of Palestinians who protesters said have been killed in the conflict.

Manar Ghanayem, 70, attended with more than a dozen friends and relatives, including small grandchildren with Palestinian flags painted on their faces.

“We came here to let our voices be heard and our hearts and hoping we’ll change the way people see this conflict,” said Ghanayem, who traveled from North Carolina. “Every human is entitled to basic human rights, not killing kids, not torturing people,” she said.

The war began Oct. 7 when gunmen from Hamas, the militant group that controls Gaza, broke through Israel’s border, killing at least 1,400 people, leaving at least 5,400 injured and taking about 240 people into Gaza as hostages, Israeli officials said.

Israel retaliated with strikes in Gaza, where at least 9,488 people have been killed and 24,000 wounded, the Gaza Health Ministry said. With that death toll heavy on their minds Saturday morning, Mahmoud Ashi and a group of friends boarded a bus in New Jersey carrying 75 small handmade body bags. Ashi, who grew up in Gaza and moved to the United States in 1987, said his group spent four days crafting the bags out of sheets and cut-up mattress pads. On the side of each bag, they wrote the name of a child killed in Gaza.

The victims include Ashi’s own brother and nephew, killed in their Gaza home Friday by a bombing in the middle of the night. Two of his nieces are hospitalized in critical condition.

“Is this [Israel’s] right to defend themselves? Killing children?” he asked, holding out a bag with the name of a 10-year-old child. “My brother lost his life when he was sleeping. My nephew lost his life when he was sleeping.”

Betoul Ajin, 22, held tight to the hand of her aunt, Zenaib Omar, 61, who is blind and immigrated to the United States from the West Bank in 1986. The women said they felt drawn to the demonstration after weeks calling their senators’ offices, which, they said, have been unresponsive. “Our senators need to be reminded that they work for us,” Ajin said.

The rally was supported by a broad coalition, including Palestinian rights groups, antiwar and climate advocates, Jewish anti-Zionist organizations, Indigenous rights groups, trans and queer liberation groups, and racial justice organizations. Moshe Berg, an ultra-Orthodox Jew attending from Rockland County, N.Y., said the actions in Israel do not represent Jewish values. Seeing Berg’s traditionally Jewish garb but not hearing his words, a protester walked by and told him, “See you in hell.”

Emotions ran high. Signs and speakers accused Israel of “genocide.” Many demonstrators chanted “from the river to the sea,” a call for freedom from the Jordan River to the Mediterranean Sea that some interpret as a call to wipe out Israel altogether.

Ron Halber, executive director of the Jewish Community Relations Council of Greater Washington, said the rhetoric at Saturday’s event was calling for the elimination of the state of Israel, which he said was acting to defend itself following a brutal terrorist attack.

The protesters, he said, “are wholeheartedly supporting a homicidal terrorist organization that slaughtered 1,400 Israelis in cold blood and has taken numerous civilians hostage including from our own country,” he said. “They are just incredibly misguided, uninformed and reactionary, and history will judge they have put themselves on the side of supporting terrorists versus a democracy trying to defend itself.”

Halber said his group discouraged supporters of Israel from attending to counterprotest. Jen Zwilling, chief executive of the Edlavitch D.C. Jewish Community Center, also emailed members Friday asking them to resist any urge to counter the event or engage with protesters, which she said could “increase the potential for violence or antisemitic rhetoric.”

D.C. police said they made one arrest in the evening for destruction of property, related to the spray-painting of the word “Gaza” on the nearby McDonald’s on 17th Street. It was not clear who the perpetrator was. Separately, someone pressed red handprints, meant to symbolize blood, onto stone pillars along the White House perimeter.

Police began to reopen streets to vehicle traffic downtown around 7 p.m., but large crowds remained in Lafayette Square Park as darkness fell, drumming and chanting slogans. Demonstrators remained along the fence line outside the White House, while thousands of others dispersed throughout the city.

Biden was the target of much of the crowds’ ire. On the stage and off it, many Saturday voiced anger at the president and threatened to oppose him when he stands for reelection next year. Boos rang out when Biden’s name was mentioned.

“Now we understand the language Biden and his party understands. The language they understand is the language of votes in 2024,” Nihad Awad, executive director of CAIR, the country’s largest Muslim advocacy group, told the crowd. “No cease-fire, no votes!” The crowd chanted it back.

“No votes in Michigan, no votes in Arizona, no votes in Georgia, no votes in Nevada, no votes in Wisconsin, no votes in Pennsylvania, no votes in Ohio!” Awad said.

“In November, we remember! In November, we remember!” the crowd said.

The president swiftly supported Israel after the Hamas attack. On Wednesday, Biden called for a humanitarian “pause” in the war but not a cease-fire.

Ghanayem said she had voted for Biden in 2020 but was outraged by his response to the war.

“I can’t believe Biden is turning a blind eye to this and gave Israel the green light,” she said.

The White House did not respond to a request for comment Saturday. But in response to similar criticism, on Friday a National Security Council spokesperson repeated that the administration did not support a cease-fire.

“We support humanitarian pauses in the fighting in order to get lifesaving humanitarian aid in and distributed to those in need in Gaza, and to get hostages out,” the spokesperson said. “What we do not support are calls for Israel to stop defending itself from Hamas terrorists, which is what a permanent cease-fire would be.”

Half of registered voters in the United States approve of Israel’s response to the Hamas attack, while 35 percent disapprove, according to Quinnipiac University polling released Thursday. Those views vary sharply by party identification, race and age, with the lowest approval seen among Democrats (33 percent), voters ages 18 to 34 (32 percent) and Black voters (29 percent).

At the same time, the polling shows, 51 percent of voters support the United States sending more military aid to Israel and 71 percent of voters support providing humanitarian aid to Palestinians in Gaza.

It was unclear Saturday how backlash and anger over the administration’s war response might actually play out in the 2024 campaign - particularly if Biden’s opponent is former president Donald Trump, a strong supporter of Israel who draws opposition for many other reasons.

“This election has become a conundrum, because I don’t want to vote for Biden,” one woman told her friend as they began marching in downtown D.C. “But I really, really don’t want to vote for Trump.”

Emily Davies, Karina Elwood, Ellie Silverman and Clarence Williams contributed to this report.