Carlos Cosme, 36, pleaded guilty Friday in federal court, Courthouse News Service reported.
"In his plea agreement, Cosme admitted that he hired co-defendant Jose Ortega Nuno to run a 'hit squad' on behalf of a multinational criminal enterprise controlled by Fernando Sanchez-Arellano," the U.S. Attorney's Office said in a statement.
Nuno, who pleaded guilty to racketeering in 2011, was also employed as a police officer with the Baja California State Attorney General's Office. He had been extradited to the United States to face charges. Another official from the police force, Jesus Quinonez Marquez, pleaded guilty to federal racketeering charges last week.
Cosme, who is the 39th person convicted in the drug ring, also pleaded guilty to selling and importing methamphetamine, prosecutors said.