The mother of fugitive Texas teen Ethan Couch, known for using an "affluenza" defense in a fatal drunken-driving accident, has been returned to the U.S. from Mexico minus her son, whose own deportation was delayed by a Mexican judge.

Tonya Couch arrived at Los Angeles International Airport on a flight from Mexico in the custody of the U.S. Marshals Service and was taken in handcuffs through the terminal to an unmarked Dodge Charger early Thursday morning. She was wearing blue street clothes and looked away from cameras as she walked, flanked by two marshals.

It was unclear why she was brought to Los Angeles instead of Texas, where she and her son live and where he was on probation for the 2013 drunken-driving crash. U.S. Marshals Service spokesman Eugene Hwang said he could not reveal any details about her trip through California or say how long she might remain here, citing security concerns in transporting someone in custody.

Richard Hunter, chief deputy for the U.S. Marshals Service in South Texas, said during a news conference in Houston on Wednesday that a three-day court injunction granted in Mexico to Ethan Couch will likely take at least two weeks to resolve.

But the injunction did not apply to Tonya Couch, who was deported immediately and put on a plane, an official with Mexico's National Immigration Institute told The Associated Press.

Ethan Couch was transported late Wednesday from a detention facility in Guadalajara to one in Mexico City, the official said. The decision to move Couch was made because the Mexico City facility for detaining migrants is larger and better equipped to hold someone for days or weeks.

Authorities believe the 18-year-old Ethan Couch, who was sentenced only to probation for the 2013 wreck in Texas, fled to Mexico with his mother in November as prosecutors investigated whether he had violated his probation. Both were taken into custody Monday after authorities said a phone call for pizza led to their capture in the resort city of Puerto Vallarta.

The ruling earlier Wednesday by the Mexican court gives a judge three days to decide whether the younger Couch has grounds to challenge his deportation based on arguments that kicking him out of the country would violate his rights.

Hunter said the legal maneuver basically takes the decision out of an immigration agent's hands and asks a higher authority to make the deportation decision. He said such cases can often take anywhere from two weeks to several months, depending on the priorities of the local courts.

"It also depends on the fact the Couches have legal counsel. And it seems to me, if they wanted to, they could pay them as much money as they want to drag this thing out," Hunter said. "We're hopeful that's not the case."

During the sentencing phase of Ethan Couch's trial, a defense expert argued that his wealthy parents coddled him into a sense of irresponsibility — a condition the expert termed "affluenza." The condition is not recognized as a medical diagnosis by the American Psychiatric Association, and its invocation during the legal proceedings drew ridicule.

"Couch continues to make a mockery of the system," said Fort Worth attorney Bill Berenson, who represented Sergio Molina, who was paralyzed and suffered severe brain damage in the crash.

Ethan Couch's attorneys in the U.S. issued a statement Wednesday saying they couldn't comment on the case because they weren't licensed to practice law in Mexico. It wasn't immediately clear which attorneys were handling the case in Mexico.

Mexican police say Couch and his mother spent three days in a rented condo at a resort development in Puerto Vallarta before finding an apartment. One of the Couches' telephones had been used to order delivery from Domino's Pizza to the condominium complex in Puerto Vallarta's old town, according to a police report issued by the Jalisco state prosecutors' office.

Agents from the prosecutors' office went to the complex, where a tourism operator told them that the people who had occupied the condo were asked to vacate because the owners were coming to stay over Christmas, the report said. The Couches then moved to an apartment, and the agents set up a surveillance operation in the surrounding streets.

On Monday evening, two people matching the Couches' description were spotted and intercepted. The police report said they behaved evasively, claimed to be carrying no IDs, gave inconsistent stories about their names and failed to provide proof of their legal migratory status in Mexico.

They were taken into custody and handed over to immigration officials.

Authorities in Texas said an arrest warrant was being issued for Tonya Couch on charges of hindering an apprehension, a third-degree felony that carries a sentence of two to 10 years in prison.

Ethan Couch was driving drunk and speeding near Fort Worth in June 2013 when he crashed into a disabled SUV, killing four people and injuring several others, including passengers in his pickup truck.

He pleaded guilty to four counts of intoxication manslaughter and two counts of intoxication assault causing serious bodily injury. A judge sentenced him in juvenile court to 10 years' probation and a stint in a rehabilitation center.

Associated Press writers E. Eduardo Castillo and Mark Stevenson in Mexico City, Elizabeth Rivera in Guadalajara, Mexico, Michael Graczyk in Houston, and Emily Schmall in Fort Worth, Texas contributed to this report.