WASHINGTON (AP) — U.S. Attorney General Eric Holder has expressed grave concern and disappointment to the Mexican government about the early release of a drug cartel leader convicted in the 1985 kidnapping, torture and murder of U.S. Drug Enforcement Administration agent Enrique “Kiki” Camarena.

In a meeting Monday at the Justice Department with Mexican Attorney General Jesús Murillo Karam, Holder said the U.S. will continue to work with Mexican counterparts to ensure that cartel leader Rafael Caro Quintero does not escape justice.