The state of Texas has started flying migrants to sanctuary cities, with the first flight arriving in Chicago on Tuesday evening, Fox News has learned, marking an escalation of Gov. Greg Abbott’s previous strategy of bussing migrants to ease the pressure on the border state.

Fox was told that the first flight left El Paso on Tuesday afternoon with 120 migrants on board and arrived at Chicago’s O’Hare Airport later in the day. Sources in Abbott’s office told Fox that all migrants signed voluntary waivers, as they do when bussed. 

The decision was partially in response to Chicago’s interference of the buses traveling to the sanctuary city. The city has launched lawsuits against companies transporting the migrants.

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Flight to Chicago

A migrant flight takes off from Texas to Chicago on Tuesday. (Gov. Greg Abbott's office)

The move from Abbott is an escalation from the strategy in place since April 2022 when he began bussing migrants first to Washington, D.C., and later expanded it to include other cities with "sanctuary" policies that forbid or limit cooperation with federal immigration enforcement.

Abbott’s office said this week that the state has bussed over 82,900 migrants to cities, including Washington, D.C.; New York City; Chicago; Philadelphia; Denver; and Los Angeles. Abbott has said the operation provides "vital relief" to border towns and has promised to keep doing it "until [President] Biden secures the border."

Critics have accused Abbott of performing an "illegal" political stunt, with the mayors of Chicago and New York in particular excoriating Abbott for the buses. Chicago Mayor Brandon Johnson this week accused Abbott of creating chaos across the country.

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Abbott NYC

Texas Gov. Greg Abbott speaks during a panel discussion at the Yale Club in New York City on Sept. 27. (Luiz C. Ribeiro/New York Daily News/Tribune News Service via Getty Images)

"The issue is not just how we respond in the city of Chicago," Johnson added. "It’s the fact we have a governor, a governor, an elected official in the state of Texas, that is placing families on buses without shoes, cold, wet, tired, hungry, afraid, traumatized, and then they come to the city of Chicago, where we have homelessness, mental health clinics that have been shut down and closed. We have people who are seeking employment. The governor of Texas needs to take a look in the mirror, with the chaos he’s causing for the people of this country."

Abbott’s press secretary, Andrew Mahaleris, told Fox News Digital that Johnson was "flat out lying."

"If he truly cared about these migrants, he would stop spreading falsehoods and complaining about a few thousand migrants being bussed into his sanctuary city," he said. "Instead, Mayor Johnson should call on President Biden to take immediate action to secure the border — something the president continues failing to do."

Meanwhile, the chaos at the border itself continues with enormous numbers of migrant encounters. The daily record for encounters was broken this week when more than 12,600 migrants were encountered in a single day.

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Customs and Border Protection sources told Fox News on Wednesday that December total migrant encounters have exceeded 190,000 and are on track to break another record for the highest monthly total, which was 269,000 in September.

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Sources told Fox that agents are averaging around 10,000 encounters a day, and Mexican sources say more are on the way.

Fox News’ Griff Jenkins and Louis Casiano contributed to this report.