SAN DIEGO -- A Mexican drug trafficker extradited to the U.S. earlier this year pleaded guilty Friday to racketeering charges connected to his work for the deadly Arellano Felix cartel.

Gilberto Higuera Guerrero, 39, was brought to San Diego in January to face federal charges here after the Mexican government took the highly unusual step of extraditing 15 people already serving time south of the border.

His older brother, 46-year-old Ismael Higuera Guerrero, also among those extradited, pleaded guilty in March to similar charges, according to court documents unsealed Friday.

The brothers were senior figures in the Arellano Felix organization, based in Tijuana, Mexico.

Ismael Higuera Guerrero admitted being a top lieutenant to the Arellano Felix brothers from 1988 until his May 2000 arrest. Authorities said he coordinated the transfer of multi-ton shipments of cocaine and marijuana from Colombia north to the U.S. via Tijuana and the border town of Mexicali, 120 miles east of San Diego.

In that capacity, he supervised his younger brother Gilberto, who admitted to assisting with the importation of cocaine into the U.S.

Both men also admitted to involvement in the kidnapping and murder of cartel "enemies" in Tijuana and Mexicali. Ismael Higuera Guerrero also admitted bribing government and law enforcement officials.

He faces 40 years in prison and agreed to forfeit $5 million. Gilberto Higuera Guerrero may be sentenced to 30 years and agreed to forfeit $1 million as part of his plea agreement.

The brothers had faced an array of drug trafficking and money laundering charges stemming from a sweeping 2003 indictment that named 11 people, including accused cartel kingpin Francisco Javier Arellano Felix.

Arellano Felix and his alleged right-hand man, Manuel Arturo Villarreal Heredia, have been in federal custody in San Diego since last August, when they were captured in a U.S. Coast Guard raid aboard a sport-fishing boat off the coast of La Paz, Mexico.

They have pleaded not guilty to charges of running a criminal enterprise, racketeering and conspiracy to commit racketeering, drug trafficking and money laundering. Both are eligible for the death penalty if they are found guilty of the crimes outlined in a December indictment.