A notorious drug lord has been released from a Mexican prison after he was convicted of killing a U.S. Drug Enforcement Administration agent 45 years ago, CBS News reported.

Ernesto "Don Neto" Fonseca Carrillo, 94, was released last weekend, according to CBS News, citing a federal agent.

Fonseca, the co-founder of the Guadalajara Cartel was found guilty in the kidnapping, torture, and murder of DEA agent Enrique "Kiki" Camarena.

While heading out for a lunch with his wife, Mika, Camarena, 37, was surrounded by five armed men who threw him into a car and sped away, CBS News reported. He had been due to transfer back to the U.S. in three weeks.

A month after his disappearance, Camarena's body was found on a ranch 60 miles away with signs of torture. Fonseca had been serving the remainder of his sentence under home confinement since being moved from prison in 2016, according to CBS News.

Camarena, a father of three, had been living in Guadalajara while working as an undercover DEA agent, spending four years working to bust Mexico's biggest marijuana and cocaine traffickers.

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