"El Mayo and Guzman Lopez join a growing list of Sinaloa cartel leaders and associates who the Justice Department is holding accountable in the United States," Mr Garland said. "Fentanyl is the deadliest drug threat our country has ever faced, and the Justice Department will not rest until every single cartel leader, member, and associate responsible for poisoning our communities is held accountable,” added Mr Garland, the top law enforcement officer in the US.

Mexican drug lord Ismael "El Mayo" Zambada and the son of his former partner, Joaquin "El Chapo" Guzman, were arrested in El Paso, Texas, on Thursday, the U.S. Justice Department said. “The Justice Department has taken into custody two additional alleged leaders of the Sinaloa Cartel, one of the most violent and powerful drug trafficking organizations in the world," the department said in a statement.

Two U.S. officials told Reuters that Zambada and Guzman Lopez were detained after landing in a private plane. Zambada is one of the most consequential traffickers in Mexico’s history and co-founded the Sinaloa Cartel with El Chapo, who was extradited to the United States in 2017 and is serving a life sentence in a maximum security prison.