Mexican drug lord Rafael Caro Quintero appeared before a judge in Brooklyn on Friday afternoon, pleading not guilty to charges related to his involvement in the decades-old killing of a Drug Enforcement Administration agent.

The move by Mexico to allow the transfer of Rafael Caro Quintero to the United States signaled a potentially new era of cooperation in the drug war.

Mexico has handed over 29 drug cartel figures to the United States, including one of the FBI’s most wanted, Rafael Caro Quintero, in what observers say is a “show of compliance” by Mexican authorities.

Both men face a range of serious charges, including drug trafficking, murder conspiracy and weapons violations.

A Mexican drug kingpin depicted in Netflix’s gritty crime drama “Narcos” was arraigned Friday in Brooklyn while wearing the handcuffs that belonged to the DEA agent he was

The Mexican drug kingpin who was brought to the United States on Thursday is accused in the 1985 kidnapping, torture and murder of DEA agent Enrique “Kiki” Camarena.