Protesters flocked to the White House Saturday to call on the Trump administration to reunite undocumented immigrant families who have been separated at the southern border in recent months.

The demonstration – a response to President Donald Trump’s “zero tolerance” immigration policy instituted in April – brought thousands of attendees to the District. The protest was one of more than 600 rallies across the nation advocating for immigration reform.

Protesters chanted, “vote them out” and “families belong together” while carrying signs calling for the abolishment of the Immigration and Customs Enforcement agency and asking officials to “uncage the children.”

[gwh_image id=”1060888″ credit=”Graeme Sloan | Contributing Photo Editor” align=”none” size=”embedded-img”]A sign reads “Our dreams are too big for your cages” at the “Families Belong Together” march.[/gwh_image]

Several celebrities – including actress America Ferrera, singer Alicia Keys and Broadway star Lin-Manuel Miranda – attended the D.C. protest, which took place under a blistering sun in 90-degree heat. Fire trucks lined the streets, turning on their hoses to cool down demonstrators.

Ferrera, in an address to the crowd, said that although Trump signed an executive order ending family separation earlier this month, the measure did not do enough to assist asylum seekers in need of help. The order allows the U.S. government to detain parents and children together for an indefinite period of time.

“I am here as a human being with a beating heart, who can feel pain, who understands compassion and who can easily imagine what it must feel like to struggle the way families are struggling right now,” Ferrera said.

[gwh_image id=”1060884″ credit=”Graeme Sloan | Contributing Photo Editor” align=”none” size=”embedded-img”]Alicia Keys waits with her son before taking the stage to speak at the at the “Families Belong Together” march.[/gwh_image]

Several public figures also spoke at the event, including a woman named Jocelyn, who did not give her last name but identified herself as a plaintiff in the American Civil Liberties Union class-action lawsuit against Trump and ICE officials.

The suit, filed in February, alleges that officials were detaining immigrants for “no legitimate purpose” and had imposed psychological damage on children who had been separated from their parents.

Jocelyn said her son was taken from her last August when they crossed the Texas border, and she didn’t know where he was for two months.

“You march to protest this cruel practice of separating children from their parents,” she said. “My son and I are together, and for that, I will be forever grateful to you.”

[gwh_image id=”1060885″ credit=”Graeme Sloan | Contributing Photo Editor” align=”none” size=”embedded-img”]A man holds a baby doll with a label that reads “Pro Se,” a legal term meaning the litigant will represent themselves instead of being represented by a lawyer. Detained undocumented immigrants, asylum seekers and their children frequently go without legal help during their detainment and hearings.[/gwh_image]

Traci Blackmon, the executive minister of justice and local church ministries for the United Church of Christ, told protesters to remember that just because the separation is legal doesn’t mean it is right.

“Legislating evils doesn’t make them holy,” she said.

Attorney General Jeff Sessions made headlines earlier this month when he used bible verses to defend the administration’s immigration policies, the New York Times reported.

Protester Cristian Pineda, a graduate student at George Mason University and a second generation immigrant, said he is personally invested in the immigration issue because his family fled from El Salvador to the U.S. in the 1980s.

“This is not a Latino issue,” he said. “This is not a U.S. issue. This is a world issue. This is a human rights issue.”

Arianna Dunham contributed reporting.