Thousands of protesters marched from Downtown Manhattan to Brooklyn on Saturday in support of migrant families who were separated when they entered the country illegally or seeking asylum.

Eighty-year-olds with “Abolish ICE” pins on their walkers joined families with babies in strollers in the “Families Belong Together” march, which started in Foley Square, the site of New York Immigration Court, and crossed Brooklyn Bridge to Cadman Plaza, near the federal courthouse.

“This is the first time in my life I’ve come out to protest. And I lived through Vietnam, through Roe v. Wade,” said Lisa Zieger, 66.

“I’m here because I’m disgusted, outraged, and frightened by our government,” the Newark resident continued. “I’ve never felt so personally threatened before. It’s important to come out, to put your body on the line.”

Eleanor Evans, 9, said it was her first protest, too. She and her sister are the children of an immigrant themselves. “We really respect the kids who have been separated from their parents,” she said. “It’s terrible.”

Eleanor was one of thousands who marched across Brooklyn Bridge, where many drivers honked in support. Organizers said 20,000 turned up, though the NYPD declined to confirm the figure.

One woman in New York City painted “We Have to Care” on the back of her dress, a reference to the coat First Lady Melania Trump wore when she went to visit detained children last week. That attire had “I really don’t care, do U?” on the back.

The focus was on the roughly 2,000 children who have been separated from their families under President Trump’s “zero-tolerance” immigration policy. The marchers continued recent weeks’ pressure on Trump, who last week signed an executive order ending his policy of separating kids from their parents at the U.S.-Texas border.

Many of the marchers also joined recent calls to abolish and replace Immigration and Customs Enforcement, the federal agency at the center of the “zero-tolerance” policy. “Abolish ICE” was a popular sign on the Brooklyn Bridge and elsewhere around the country.

That idea was the topic of two Saturday morning tweets from Trump, who reassured “the brave men and women of ICE, do not worry or lose your spirit” and said they were doing a “fantastic job.”

The protesters saw things differently.

“This is our ‘throw your body on the gears of the machine’ moment,” said David Siffert, 34, of the East Village, who marched in a suit despite heat that reached over 90 degrees. “I came from the airport to be here. It’s important. It shows people how we feel. If people are willing to show up in the streets for something, they’re going to vote for it.”

Dorrie Lubowsky, 55, of Midwood, Brooklyn, said she was there because she is a child of two Holocaust survivors.

“I know what the lasting affect of this is,” she said. “We’ve got to come out while we still have a voice to be heard. I’m seriously worried.”

In Queens, about 2,000 people marched from Jackson Heights to Astoria. The demonstrators included Alexandria Ocasio-Cortez, who defeated the powerful Rep. Joseph Crowley in Tuesday’s Democratic primary.

She urged the marchers to keep fighting against “displacement and fear.”

“I am confident and hopeful that it will not last long and that it will not last forever, because of every single individual who’s on this block today,” Ocasio-Cortez told the crowd.

Mayor Bill de Blasio offered support for the marchers while attending a citizenship event at the John Jay College of Criminal Justice.

“We need comprehensive immigration reform and we need new agencies to replace ICE,” he said. “There’s a way to handle immigration properly, and we have to start working for that day.”