Federal, state and local authorities arrested people named in two federal grand jury indictments that contend the gang allied with the cartel and a southern Los Angeles County street gang to run drugs and guns.
The crackdown included Michael "Boo" Moreno, 55, of Fresno and Jimmy Ruben Soto, 77, of Visalia. Authorities said both men are alledged members of the Mexican Mafia.
"Today's salvo against the Mexican Mafia is part of a 20-year fight to curb the influence of the prison gang both inside prison walls and on the streets of Southern California," U.S. Attorney Andre Birotte Jr. said in a statement.
Authorities have long contended that the Mexican Mafia controls drug-dealing and other criminal activities by local Hispanic street gangs from behind bars.
Authorities arrested eight of 13 people named in an indictment that claims the Mexican Mafia formed an alliance known as the "Project" with La Familia Michoacana. In exchange for drugs and money, the Michoacan-based cartel was allowed to sell methamphetamine and marijuana in Southern California and the Mexican Mafia agreed to protect imprisoned members, according to the July indictment.
Local street gangs were ordered to protect La Familia drug shipments and to collect drug debts, according to the indictment.
La Familia Michoacana and it successor, Los Caballeros Templarios (the Knights Templar), have shipped hundreds of thousands of pounds of drugs into the United States, the indictment said.
"The successful results of this joint operation allowed law enforcement to intervene in the development of a very strong and powerful merger between dangerous criminal organizations," Los Angeles County Sheriff Lee Baca said. "We believe that we have initiated a crippling effect to those members who are still loyal to the Mexican Mafia criminal organization."
Authorities also arrested 14 of 31 people named in racketeering indictment that contends the Mexican Mafia used the Florencia 13 street gang to make money through drug- and gun-running, illegal gambling, extortion and fraud.
"Florencia 13 is one of the largest, most powerful and oldest street gangs in Southern California. Several members of the gang have risen through its ranks to become leaders of the Mexican Mafia," the U.S. attorney's office statement said.
Last week's indictment contended that key members of the Florencia 13 gang are behind bars but manage to run the gang through smuggled instructions.
Others named in the indictments already are in custody or on the run, authorities said.
The three-year investigation that led to the indictments resulted in the seizure of 600 pounds of meth and state charges were filed against six people, authorities said.
The Associated Press contributed to this story.