The Texas teenager who infamously invoked an “affluenza” defense while on trial for a fatal drunken-driving crash could be on a plane back to the U.S. later Tuesday, Mexican authorities told NBC News.

Ethan Couch, who had been on the lam in Mexico with his mother Tonya before being caught Monday, will be flying to Houston from Puerto Vallarta, said Ricardo Ariel Vera Lira, a federal delegate in the state of Jalisco.

"It was a very high priority for us to make sure that we found him and got him back," Tarrant County Sheriff Dee Anderson said of the 18-year-old Couch.

Couch and his mom fled over the border earlier this month in a pickup truck and headed to the coastal resort city where they tried to blend in with the hordes of American tourists spending Christmas there, Anderson said.

The teenage fugitive dyed his fair hair a darker shade and was living a "cash existence" in an attempt to elude authorities, the sheriff said.

The pair was caught at 6 p.m. Monday, when they were seized near the town's popular boardwalk by Mexican authorities at the request of the FBI and U.S. Marshals, Anderson said.

Couch was sentenced in juvenile court and is serving 10 years of probation for killing four people and injuring nine others in a drunken crash in 2013.

He is scheduled to be back in juvenile court on Jan. 19 at which time prosecutors will ask that his case will be transferred to adult court.

If the judge denies that, Couch will be jailed in a juvenile facility for four moths until April 11 when he turns 19.

"That is not enough," Anderson said. "I would like to see him placed in an adult prison to serve out the remainder of his sentence."

Tonya Couch, 48, faces charges of hindering apprehension, the sheriff added.

Couch's lawyers said in a statement they had not yet spoken with the teenager.

Police began searching for Couch after he missed an appointment with his probation officer. His case drew nationwide attention after his lawyers used his privileged upbringing as part of their defense at his manslaughter trial.

Couch was convicted of four counts of intoxication manslaughter after he lost control of his car and plowed into a group of pedestrians on June 15, 2013 in Burleson, Texas.

In addition to the four dead, nine others were injured. At the time, Couch was 16 and had a blood-alcohol level three times the legal limit.

A photo of Ethan Couch provided by Mexico's attorney general for the state of Jalisco. Attorney General State of Jalisco

Even though Couch admitted to the crime, he managed to escape doing prison time thanks in part to an unusual defense strategy employed by his lawyers. They put on the stand a psychologist who testified that Couch was afflicted with "affluenza," which made him unable to distinguish right from wrong due to his privileged upbringing. They argued Couch needed rehab not prison.

Affluenza is not recognized by the American Psychiatric Association as an official diagnosis. But Judge Jean Boyd bought it and sentenced Couch to 10 years probation, igniting a firestorm of criticism.

Couch returned to the spotlight earlier this month, when officials went to the house where he had reportedly been staying at with his mom and found it empty — save for a pinball machine, Reuters reported.

Couch and his mother apparently fled after video emerged earlier this month on Twitter which showed a group of young people playing beer pong. The person who posted the video claimed Couch — who is not allowed to drink or use drugs and drive — was in the video and was violating his court terms.

Couch met with his probation officer around the time the video surfaced, and as the Tarrant County DA began investigating whether he was in the footage. But he didn't show up for his next appointment.

"They had planned to disappear," Anderson said. "They even had something that was almost akin to a going away party before they left town."