Drug lord Ernesto “Don Neto” Fonseca Carrillo, who was convicted in the 1985 killing of a U.S. Drug Enforcement Administration agent, was freed from prison after completing his 40-year sentence, a federal agent confirmed late Wednesday.

Fonseca, 94, had been serving the remainder of his sentence under home confinement outside Mexico City since being moved from prison in 2016. The federal agent, who requested anonymity because they were not authorized to speak publicly about the case, said he was released last weekend.

The co-founder of the Guadalajara Cartel along with Rafael Caro Quintero, Fonseca was convicted in the kidnapping, torture and murder of DEA agent Enrique “Kiki” Camarena.

Caro Quintero, who was also convicted in the murder, was one of 29 cartel figures Mexico sent to the United States in February.

It was not immediately clear if the United States would also seek Fonseca.

Fonseca was arrested in Puerto Vallarta in 1985. (ABC News)