An American Airlines plane takes off from Los Los Angeles International Airport. (Mike Blake/Reuters)

Several U.S.-based airlines asked the federal government Wednesday to refrain from using their planes to transport migrant children separated from their families, saying the controversial Trump administration practice does not align with their values.

The announcements by American, United and Frontier airlines came amid reports that the president would sign an executive order ending family separations at the U.S.-Mexico border, with more airlines later following suit.

The companies’ attempts to distance themselves from the controversial policy prompted a sharp rebuke from Tyler Houlton, a Department of Homeland Security spokesman, who accused the corporations of “Buckling to a false media narrative” on Twitter.

In a statement, United chief executive Oscar Munoz said the company was “concerned about reports that commercial airlines have been used to transport immigrant children from their parents.”

In a news release, American said that “We have no desire to be associated with separating families, or worse, to profit from it,” adding that it had carried refugees for nonprofits and for the government, most often for the purpose of reuniting them with family members.

Frontier released a similar statement Wednesday afternoon.

The three airlines all said they do not think their planes have been used to transport migrant children who had recently been separated from their parents.

More than 2,300 children have been separated from their parents as a direct result of the decision to criminally charge people caught crossing the border illegally.

The practice has drawn criticism from political and religious leaders, including conservatives such as former first lady Laura Bush and Sen. Ben Sasse (R-Neb.).

On Wednesday afternoon, Trump abruptly signed an executive order that administration officials said would keep families together in federal custody while awaiting prosecution for illegal border crossings. In a statement, Delta praised the order and called reports of families being separated “disheartening.” Southwest Airlines said the company did not “wish to have any involvement in the process of separating children from their parents” and does not have “evidence that tickets purchased for Southwest flights have been utilized to transport detained children.”

But animus toward the practice has been growing in the airline industry, particularly with workers who say they don’t want to help implement a government policy they find morally wrong.

In an editorial for the Houston Chronicle, flight attendant Hunt Palmquist said he had worked two flights during which U.S. Immigration and Customs Enforcement agents were flying migrant children as young as 4 to a “relocation” site.

He did not reveal which airline he worked for in the editorial or in a Facebook post, but he said the incidents had remained with him.

“Since working the two flights, the images of those helpless children have burned into my psyche,” he wrote. “The little children whose faces were full of fear, confusion, sadness and exhaustion left me somewhat traumatized as it occurred to me a few weeks later that I might as well have been a collaborator in their transport.

” . . . I will no longer be complicit and will walk away from any future flight assignments that try to make me a pawn for this disgusting and deplorable cause.”

The Arizona Republic reported that the flight was probably operated by American Airlines, although a company spokeswoman told the publication that the airline doesn’t disclose passenger manifests.

The Washington Post could not independently confirm the details of Palmquist’s account.

The airlines were not the first companies to speak out against the separation of families at the border. Apple chief executive Tim Cook said in Dublin on Tuesday that “what’s happening is inhumane; it needs to stop.” The heads of Uber, Twitter and Google have also weighed in, while Facebook’s Mark Zuckerberg has encouraged people to donate to a legal aid organization.

Some businesses have been caught up in the heightened immigration crackdown.

Microsoft faced outrage online recently for a January blog post saying that the company was “proud to support” ICE’s IT. The company published a statement Monday that “Microsoft is not working with U.S. Immigration and Customs Enforcement or U.S. Customs and Border Protection on any projects related to separating children from their families at the border.”

The American Civil Liberties Union and members of Congress have also called on private bus line Greyhound to stop letting Border Patrol agents conduct raids on board. A company spokeswoman, Lanesha Gipson, said Greyhound doesn’t “support or coordinate these searches, nor are we happy about them,” adding that Greyhound is simply complying with the law.

Jena McGregor contributed to this report. 

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