Drug Kingpin Convicted of Killing D.E.A. Agent Is Captured in Mexico

MEXICO CITY — A drug kingpin convicted of orchestrating the torture and murder of a Drug Enforcement Agent was captured in northern Mexico on Friday, according to Mexican officials, bringing a case that has long been a source of tension with the United States one step closer to resolution.

The drug boss, Rafael Caro Quintero, was captured in a joint operation involving the Mexican marines and the country’s prosecutor’s office near the town of San Simón in the state of Sinaloa, Mexican officials said.

A warrant for Mr. Caro Quintero’s arrest had been issued to pave the way for his extradition to the United States, officials said.

Mr. Caro Quintero was convicted of masterminding the 1985 killing of the D.E.A. agent Enrique Camarena, who was known as Kiki, and was placed on the F.B.I.’s 10 most wanted list in 2018, after he had been released in 2013 on a legal technicality. He has been on the run ever since.

In a move that took American authorities by surprise, Mr. Caro Quintero had served 28 years of his 40-year sentence when he was abruptly set free by a judge who ruled that he had been improperly tried in federal court rather than a state court for the murder of Mr. Camarena.

The torture and killing of Mr. Camarena, who had been working undercover, was considered an inflection point in Mexico’s violent war on drug cartels, and has long been a sore spot for U.S. law enforcement officials, as well as a source of friction with Washington.

The United States had been seeking Mr. Caro Quintero’s extradition at the time of his release. He had long maintained that he did not direct Mr. Camarena’s killing.

The capture of the infamous drug boss, who was a founder of the now-defunct Guadalajara Cartel, comes just days after President Andrés Manuel López Obrador of Mexico met with President Biden in Washington.

In a joint statement after the meeting, both leaders said they had “reaffirmed our commitment to work together to address major security issues affecting our nations, including the challenges of fentanyl, arms trafficking, and human smuggling.”

The capture of Mr. Caro Quintero is also likely to be viewed as an important victory for Mr. López Obrador, who has presided over one of the bloodiest periods in Mexican history, despite promising to tackle crime and quell violence.