The U.S. Treasury Department on Tuesday sanctioned 21 people and 25 companies tied to the Sinaloa Cartel faction led by Ismael Zambada Sicairos, known as Mayito Flaco, and put the former husband of the governor of Baja California at the center of what it called a narco-corruption scheme.

The Treasury’s Office of Foreign Assets Control said “this Sinaloa Cartel-enabled narco-corruption has reached the highest levels of the Baja California state government. At the center of this narco-corruption scheme is the ex-husband of the Governor of Baja California, Carlos Torres, and his brother Luis Torres.” Mr. Torres was until recently married to Gov. Marina del Pilar Ávila, of Mexico’s governing Morena party.

The couple’s troubles became public in May, when they announced that the United States had canceled their visas. Media reports soon tied Mr. Torres to organized crime; Ms. Ávila announced their separation at the end of the year, and in January Televisa’s N+ Focus reported that Mexico’s attorney general’s office was investigating him over alleged criminal links, which was later confirmed. Mr. Torres said at the time that “it is not an investigation based on facts.” The governor said she was convinced the attorney general’s office, “an extremely serious institution,” would conduct a thorough inquiry and that “the facts will be clarified.”

OFAC accuses Mr. Torres of using “his political influence to facilitate cartel activities and protect the Sinaloa Cartel from government and law enforcement intervention in Baja California.” It says he was allied with Juan José Ponce Félix, alias El Ruso, the Mayito Flaco organization’s strongman in Mexicali, and that he received cartel payments through Pedro Mendivil, Mexicali’s former public security director. Mr. Mendivil was arrested in July on charges of forced disappearance, vehicle theft and criminal association, and was later released.

The designation also connects Mr. Torres to Rafael Buenrostro Marín, a former Customs official posted to Chihuahua and a former legislative adviser to the Baja California state government. The Treasury places Mr. Buenrostro near another faction leader, José Ángel Rivera Zazueta, alias Don Flaco, who was arrested last week in Mexico City. The authorities described him as a coordinator and financier of an operation moving chemical precursors from China to Mexico and the United States.

After the announcement, the Mexican government’s Financial Intelligence Unit said it would add those named in OFAC’s designation, Mr. Torres among them, to its Blocked Persons List “as a preventive measure of an administrative nature.”

The Treasury statement also maps the organization’s inner circles in detail for the first time. The brothers Jorge Luis and Francisco Mendoza Uriarte, operatives the younger Zambada inherited from his father, belong to his close group; Jorge Luis, alias Güero Chompas, “is now the head of security for Los Mayos,” the agency said. So does Hildegardo Gastelum García, alias Aldo, described as one of Mayito Flaco’s most trusted advisers, a significant drug trafficker and the owner of a Culiacán hotel business whose illicit revenue finances Los Mayos’ war against the Chapitos.

That war dates to July 2024, when the elder Zambada, Ismael Mayo Zambada, was arrested in Culiacán after the sons of his old partner, Joaquín Guzmán, known as El Chapo, betrayed him and handed him to U.S. authorities. The split between Los Mayos and Los Chapitos has since left thousands of people murdered or disappeared in Sinaloa. Los Chapitos, also pressed hard by the authorities, had seemed the weaker side, but arrests of Mayito Flaco’s people have risen in recent months. The war shows no sign of ending.