As Air Force One shuttled President Trump back to Washington following a boisterous heartland rally on Wednesday, hundreds of people filled the terminals at the president’s hometown airport.

The spontaneous demonstration at New York City’s LaGuardia was sparked by rumors of the arrival of migrant children separated from their parents at the southern border. Waving signs and singing songs in English and Spanish, the crowd was both a welcoming party and rebuke of the White House policies that have split the country in recent days.

More than 2,300 children have been separated under the administration’s “zero tolerance” policy to criminally charge adult migrants. Although Trump signed an executive order ending family separation on Wednesday, outrage continues to build – including at LaGuardia.

“We’ve been here since 10 p.m. when we heard there were young people on flights coming from Texas and other places,” a woman named Luba, who identified herself as the immigrant defense coordinator with the activist group Make the Road New York, told The Washington Post early Thursday. “We’re here to welcome anyone who comes, especially young people.”

Although demonstrators had yet to see children deplaning by 1 a.m., the crowd of approximately 300 remained at the airport, Luba said. Others claimed online to have spotted groups of unaccompanied minors inside the terminals.

Footage from LaGuardia showed lines of individuals hoisting signs – such as “Trump Does Not Speak for Us” and “Keep Families Together” – and crowds singing Mexican folk anthem “Cielito Lindo” and the civil rights hymn “Ain’t Gonna Let Nobody Turn Me Around.”

In a video posted on Twitter by the activist group Bend The Arc, the group’s CEO Stosh Cotler explained to the LaGuardia crowd how the demonstration started.

“Tonight at about 7:30 I received a text from a woman on an American Airlines flight, who saw about seven young people being transported from Texas to LaGuardia,” Cotler told the crowd, according to the clip. “This incredible woman . . . just saw something she knew was wrong and took action.”

She then reached out to Cristina Jimenez, the co-founder and executive director of United We Dream, an immigrant youth organization. According to Cotler, the pair raced to LaGuardia to meet the plane but missed the children. Jimenez then shared a photo of the youths purportedly taken on the flight from Texas at 10:27 p.m. Demonstrators began gathering at the airport, anticipating other flights carrying separated children.

Cristina Jimenez tweeted “Come out to LaGuardia airport terminal C to stand w/ immigrant brother & sisters criminalized by Trump for seeking refugee. We must stop Trump’s deportation force. Join us to demand #FreedomForImmgrants#[email protected]@[email protected]

“It all happened within an hour,” Luba told The Post. “We stopped what we were doing and rushed. It caught on like wildfire.”

On Wednesday, American Airlines, joined by other major air carriers United and Frontier, distanced itself from the Trump administration’s policy. Acknowledging the government has used American flights to transport refugees in the past, the airline said in a statement the company has “no knowledge that the federal government has used American to transport children who have been separated from their parents due to the recent immigration policy, but we would be extremely disappointed to learn that is the case.”

The airline requested that government refrain from using American flights for separated migrant children. “We have no desire to be associated with separating families, or worse, to profit from it,” the statement said.

But children from the border have begun being filtered into New York City “under cover of darkness,” as the New York Times put it. On Wednesday, Mayor Bill de Blasio revealed 350 unaccompanied minors have recently come through a Harlem social service agency that contracts with the federal government. According to the Times, 239 children are currently in the agency’s care.

At a news conference Wednesday, de Blasio lashed out at the federal government’s relocation.

“How is it possible that none of us knew that there were 239 kids right here in our own city,” the mayor said, the Times reported. “How is the federal government holding back that information from the people of this city and holding back the help these kids could need?”

Demonstrators continued to sing and fill up the LaGuardia terminals into the early morning. Before thinning, people in the crowd slapped their hands in unison and joined their voices in a chant.

“I believe that we will win!” they shouted into the terminal, according to video footage. “I believe that we will win!”