WASHINGTON – A federal judge in Washington halted an apparent deportation-in-progress Thursday and threatened to hold Attorney General Jeff Sessions in contempt after learning that the Trump administration tried to remove a woman and her daughter while a court hearing appealing their deportations was underway.

"This is pretty outrageous," said U.S. District Court Judge Emmet G. Sullivan after being told about the removal. "That someone seeking justice in U.S. court is spirited away while her attorneys are arguing for justice for her?"

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"I'm not happy about this at all," the judge continued. "This is not acceptable."

The woman, known in court papers as Carmen, is a plaintiff in a lawsuit filed this week by the American Civil Liberties Union that challenges a recent decision by Sessions to exclude domestic and gang violence as reasons that people can qualify for asylum in the United States.

Attorneys for the civil rights organization and the U.S. Department of Justice had agreed to delay removal proceedings for Carmen until 11:59 p.m. Thursday so they could argue the matter in court.

But lead ACLU attorney Jennifer Chang Newell, who was participating in the court hearing via phone from her office in California, received an email during the hearing that said the mother and daughter were being deported.

During a brief recess, she told her colleagues the pair had been taken from a family detention center in Dilley, Texas, and were headed to the airport in San Antonio for an 8:15 a.m. flight.

Justice Department attorney Erez Reuveni said he had not been told the deportation was happening that morning, and could not confirm the whereabouts of Carmen and her daughter.

The ACLU said later that government attorneys confirmed to them after the hearing that the pair was on a flight en route to El Salvador. The Justice Department said they would be flown back to Texas and returned to the detention center after landing, the ACLU said.

Calls and emails to the Justice Department's communications office were not immediately returned Thursday afternoon.

"Obviously my heart sank when I found out," Chang Newell said. "The whole point of this was to get a ruling from the court before they could be placed in danger."

To qualify for asylum, migrants must show that they have a fear of persecution in their native country based on their race, religion, nationality, political opinion or membership in a "particular social group," a category that in the past has included victims of domestic violence and other abuse.

Carmen fled El Salvador with her daughter in June, according to court records, fearing they would be killed by gang members who had demanded she pay them monthly or suffer consequences. Several coworkers at the factory where Carmen worked had been murdered, and her husband is also abusive, the records state.

Under the fast-track removal system, created in 1996 under President Bill Clinton, asylum seekers are interviewed by an asylum officer to determine whether they have a "credible fear" of returning home. Those who pass get a full hearing in immigration court.

In June, Sessions vacated a 2016 Board of Immigration Appeals court case that granted asylum to an abused woman from El Salvador. As part of that decision, Sessions said gang and domestic violence in most cases would no longer be grounds for receiving asylum.

"The mere fact that a country may have problems effectively policing certain crimes – such as domestic violence or gang violence – or that certain populations are more likely to be victims of crime, cannot itself establish an asylum claim," Sessions wrote at the time.

The ACLU lawsuit was filed on behalf of 12 migrants from Honduras, El Salvador and Guatemala – eight women, one man and three children. All failed their initial "credible fear" interviews.

Two of the children and their mothers were deported before the suit was filed; the rest were being detained in Texas and New York.

None of the adults had been separated from their children as part of President Donald Trump's "zero-tolerance" policy.

The lawsuit says Sessions's ruling, and updated guidelines for asylum officers that the U.S. Department of Homeland Security issued a month later, subject migrants in expedited removal proceedings to an "unlawful screening standard" that deprives them of their rights under federal law.

Asylum seekers previously had to show that the government in their native country was "unable or unwilling" to protect them. But now they have to show that the government "condones" the violence or "is completely helpless" to protect them, the lawsuit says.