Mexico's federal police have captured a US-born drug lieutenant who joined the Tijuana cartel after a crackdown on the Arellano Felix brothers caused the group to splinter and emerge with a younger leadership, officials said.
Armando Villareal Heredia, 33, is a San Diego native accused of trafficking drugs from the northern state of Sinaloa into the United States, federal police said in a statement.
Villareal is also wanted by the US on federal conspiracy and racketeering charges, according to a 2010 complaint that alleges murder, kidnapping and other crimes in both Mexico and California.
Named in the most-wanted list of the US Drug Enforcement Administration's San Diego region, Villareal is among 43 defendants charged by the US Attorney.
Mexican and US authorities said Villareal takes orders from Fernando Sanchez Arellano, aka The Engineer, a drug kingpin who is the leader of a younger but weaker Tijuana cartel.
Sanchez, who is in his 30s, is a nephew of the four Arellano Felix brothers who have been either killed or arrested since 2006.
In the complaint, US officials say Sanchez's criminal organisation is an offshoot of the defunct Arellano Felix cartel, whose domination of Tijuana was fictionally portrayed in the Hollywood movie Traffic.
Federal police arrested Villareal on Saturday in the northern city of Hermosillo.
Justice Department spokeswoman Debra Hartman confirmed Villareal was a US citizen. Ms Hartman did not want to comment on a possible extradition request.
In the past, Mexican authorities have captured other drug cartel members born in the US. Last August Mexican authorities captured a Texas-born drug kingpin Edgar Valdez Villarreal, known as La Barbie.