Authorities tracked the Texas 'affluenza' teen to Mexico from a phone call to Domino's Pizza

Texas teen Ethan Couch was tracked to Mexico based on a phone call made by either him or his mother to order Domino's Pizza, according to a police report from the Jalisco state prosecutors' office reviewed by the Associated Press.

Couch, 18, was serving 10 years of probation for killing four people while driving drunk when he was 16.

He "became known as the 'affluenza' teen during his trial in juvenile court, when a psychologist said he was so wealthy and spoiled he could not tell the difference between right and wrong," according to Reuters.

Couch was caught in Mexico on Monday along with his mother Tonya Couch. Authorities determined their location, the AP reports, after "one of the Couches' telephones had been used to order delivery from Domino's Pizza to a condominium complex in Puerto Vallarta's old town, far from the glitzy resorts of the city's newer section."

Tarrant County Sheriff Dee Anderson said at a press conference on Tuesday that Couch had "something akin to a going away party" before heading to Mexico earlier this month, showing that the trip was premeditated.

The Couches are expected to be returned to the US on Wednesday.