The former leader of the Tijuana drug cartel was murdered this weekend during a family party in Los Cabos, a resort city in the northwestern Mexican state of Baja California Sur, state officials said.
Francisco Rafael Arellano Felix was gunned down Friday night, special state prosecutor Isai Arias said.
The drug lord's body was identified by relatives early Saturday, the special state prosecutor said.
Several eyewitnesses gave investigators statements about the shooting at the family party, Arias said.
"Arellano Felix was shot twice, once in the chest and again in the head, causing his death. The incident occurred around 8:00 p.m. (on Friday), leading to a large deployment of state security forces and the armed forces," the special state prosecutor said.
Checkpoints were set up on highways in the area, but no arrests have been made, Arias said.
Arellano Felix was shot at a children's party by a man dressed as a clown, some media reports said.
The 63-year-old Arellano Felix was shot in the head and was finished off when he dropped to the floor at the residence where the party was being held, the Tribuna de Los Cabos newspaper reported.
The gunman managed to escape from the house, Tribuna de Los Cabos said.
Other media outlets reported that three gunmen were involved in the attack, with some stories saying the drug lord was killed at a hotel.
Arellano Felix was arrested in 1993 and received a 10-year prison sentence after being convicted on drug, bribery and arms charges.
The U.S. government requested his extradition as he was finishing his prison term in September 2003.
A California court had issued an arrest warrant for Arellano Felix on drug charges in 1980.
A Mexican court authorized the drug lord's extradition in 2004 and he was sent to the United States to face trial.
Arellano Felix was deported to Mexico in 2008 after the charges against him were reduced.
Some Mexican media outlets identified him as the former leader of the Tijuana cartel, which is also known as the Arellano Felix organization.
The cartel controlled smuggling routes through Tijuana, a border city located near San Diego, California, for more than 20 years, but the criminal organization began to unravel following the death of Ramon Arellano Felix at the hands of Mexican police in 2002.
The Tijuana cartel, once one of Mexico's most powerful criminal organizations, has been weakened dramatically in recent years by the arrests of some of its top leaders.
The Sinaloa cartel, Mexico's largest drug trafficking organization, and the Juarez cartel have also grabbed large pieces of the Arellano Felix gang's business.
Benjamin Arellano Felix was extradited to the United States in 2011, convicted on drug charges and sentenced to 25 years in prison by a federal court in April.
Eduardo Arellano Felix, one of the cartel's other bosses, was sentenced to a 15-year prison term in August by a U.S. court, while another brother, Francisco Javier, is serving a life sentence after being captured by the U.S. Coast Guard in 2006 and later convicted on drug charges. EFE