Protesters of Trump immigration policy flood streets across U.S.

They wore white. They shook their fists in the air. They carried signs reading: “No more children in cages,” and “What’s next? Concentration Camps?”

In major cities and tiny towns, marchers gathered across America, moved by accounts of children separated from their parents at the U.S.-Mexico border, in the latest act of mass resistance against President Donald Trump’s immigration policies.

“I’m hoping that decent human beings come together, and enough is enough, we’re taking out country back over, that evil is not going to prevail,” said Patricia Carlan, a grandmother of nine from Danville, Indiana, among hundreds who gathered at her state’s capital.

More than 700 planned marches drew hundreds of thousands of people across the country, from immigrant-friendly cities like New York and Los Angeles to conservative Appalachia and Indiana to the front lawn of a Border Patrol station in McAllen, Texas, near a detention centre where migrant children were being held in cages.

There, people held American and Texas flags and signs depicting a migrant father, mother and child as the Holy Family with haloed heads travelling through the desert.

In New York City, Trump’s hometown, thousands of marchers poured across the Brooklyn Bridge in sweltering 90-degree heat, chanting “shame!” and “Donald Trump must go!” Drivers honked their horns in support.

“It’s important for this administration to know that these policies that rip apart families _ that treat people as less than human, like they’re vermin_ are not the way of God, they are not the law of love,” said the Rev. Julie Hoplamazian, an Episcopal priest marching in Brooklyn, whose own grandparents fled to the U.S. during the Armenian genocide.

“Jesus was a refugee,” she said.

In Washington, a massive crowd gathered in Lafayette Park across from the White House in what was expected to be the largest of the day’s protests.

Lin-Manuel Miranda, the creator of the musical “Hamilton,” sang a lullaby dedicated to parents who are unable to sing to their children. Singer-songwriter Alicia Keys brought her 7-year-old son, and read a letter written by a woman whose child had been taken away from her at the border.

“It’s upsetting. Families being separated, children in cages,” said Emilia Ramos, a cleaner in the district, fighting tears at the rally. “Seeing everyone together for this cause, it’s emotional.”

Around her, thousands waved signs: “I care, do you?” some read, referencing a jacket the first lady wore when visiting child migrants amid the global furor over the administration’s zero-tolerance policy that forced the separation of more than 2,000 children from their parents. Her jacket had “I really don’t care, do U?” scrawled across the back, and that message has become a rallying cry for Saturday’s protesters.

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“We care!” marchers shouted outside city hall in Dallas. Organizer Michelle Wentz says opposition to the administration’s “barbaric and inhumane” policy has seemed to cross political party lines. Marchers’ signs read “Compassion not cruelty” and “November is coming.”

Trump took to Twitter on Saturday morning to show his support for Immigration and Customs Enforcement amid calls from some Democrats for major changes to immigration enforcement.

Tweeting from New Jersey, Trump said that Democrats “are making a strong push to abolish ICE, one of the smartest, toughest and most spirited law enforcement groups of men and women that I have ever seen.” He urged ICE agents to “not worry or lose your spirit.”

Though many who show up to the rallies across the country were seasoned anti-Trump demonstrators, others were new to immigration activism, including parents who say they feel compelled to show up after heart-wrenching accounts of children forcibly taken from their families as they crossed the border illegally. In Portland, Oregon, for example, several stay-at-home moms have organized their first rally while caring for young kids.

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“I’m not a radical, and I’m not an activist,” said Kate Sharaf, a Portland co-organizer. “I just reached a point where I felt I had to do more.”

Immigrant advocacy groups say they’re thrilled to see the issue gaining traction.

“Honestly, I am blown away. I have literally never seen Americans show up for immigrants like this,” said Jess Morales Rocketto, political director at the National Domestic Workers Alliance, which represents nannies, housekeepers and caregivers. “

READ MORE: Migrants meet with hostility, no matter which side of the Atlantic they land on

All across the country, groups came together in city parks and downtown squares, and photos quickly started ricocheting around social media.

Some carried tiny white onesies. “What if it was your child?” was written on one. “No family jails,” said another.

Other protesters converged on the international bridge that carries traffic between El Paso and Juarez, Mexico. They carried signs with slogans like “We are all immigrants” as they chanted “Love, not hate, makes America great.”

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Marchers gathered in Raleigh, in Pittsburgh, in Louisville, in Houston, in Antler, North Dakota, population 27.

Margarita Perez held up a Mexican flag as speakers addressed the crowd in Albuquerque. She said she was worried about the children taken from their families, and their parents left without knowing how to find them.

“Those children that they are incarcerating and separating, they are our future generations. We need to provide for these children,” she said. “They will be our future leaders.”

The city’s Democratic mayor took the microphone and declared they were there to “resist,” and the crowd erupted in a roar.