Jalisco state prosecutor Eduardo Almaguer Ramírez says U.S. authorities had asked Mexican police to help capture Ethan Couch and his mother, Tonya Couch.
Mexican detectives started looking for them starting Dec. 24, before finally catching up with them at about 6 p.m. on Monday. The pair did not resist arrest.
Couch, now 18, was placed on probation after a deadly drunken driving wreck but fled the country as authorities began investigating whether he violated terms of his sentence. He was known for using an "affluenza" defense.
Almaguer Ramírez told a news conference in Guadalajara, the capital of the Mexican state of Jalisco, that U.S. authorities knew the mother and son were in nearby Puerto Vallarta on the Pacific Coast.
The two are being held in Guadalajara before being returned to the United States.
Couch and his mother stayed first at a resort known as Los Tules, near the beach. Prosecutors say a woman who worked there helped authorities capture them.
A Mexican immigration official says a Texas woman and her son, a teen known for invoking an "affluenza" defense after a deadly drunken driving wreck, will be returning to the United States on Wednesday.
The official, who is not authorized to be quoted by name, told Associated Press reporter E. Eduardo Castillo that there are no seats available on commercial flights to allow a Tuesday return.
The official said Ethan Couch and his mother, Tonya Couch, will stay at immigration facilities in Jalisco's state capital, Guadalajara, where they will be given food and rooms with beds.
