Nineteen people have been charged as part of a three-year investigation into the Mexican Mafia prison gang, a powerful and violent group that uses street gangs to traffic drugs both inside and outside Southern California correctional facilities.

“Operation Emero” captured thousands of recorded conversations and written communications which revealed how Mexican Mafia members used prison phones, smuggled cellphones, mail and email to operate their illicit empires from behind bars, the District Attorney’s Office said Friday.

The gang’s underlings were ordered to extort victims, sell drugs and collect money for members serving prison time, according to authorities.

Prosecutors did not specify which prisons were involved, or how many.


The task force operation — led by the Sheriff’s Department, FBI and state Department of Corrections and Rehabilitation — culminated Thursday with 10 arrests. During the takedowns Thursday authorities also seized $51,000 in cash, methamphetamine and heroin.

Nineteen people — most described as active gang members with prior criminal convictions — have been charged overall. Prosecutors did not specify if any of the defendants were inmates or say where they were arrested.

The charges against them include conspiracy to commit torture, conspiracy to commit assault causing great bodily injury, extortion, possession of drugs for sale, conspiracy to commit arson and possession of an assault weapon. Eighteen are set to be arraigned Monday in San Diego Superior Court, while one defendant remains at large.

According to the investigation, the defendants operated in two groups, led by either federal prisoner Jose Alberto “Bat” Marquez or California death row inmate Ronaldo Ayala.


Jose “Bat” Márquez is shown in 2003 by State Ministerial Police in Tijuana. (Handout photo)

Marquez, a Mexican Mafia member, has been in federal custody since being extradited from Mexico in January 2007.

Before that, he worked as an alleged enforcer for Tijuana’s Arellano-Felix drug trafficking organization, and Mexican authorities in 2003 linked him to at least 20 killings there, including one of the country’s most notorious: the 1993 shooting of Guadalajara Cardinal Jesus Posadas Ocampo.

As he was awaiting trial on drug-trafficking charges in April 2007, he orchestrated a meth deal from his cell. Already convicted of two prior drug-trafficking felonies, Marquez was sentenced to life in prison following a 2011 jury trial, the FBI said at the time.


Ronaldo Ayala is sentenced to death in 1989. (U-T file photo)

Ayala has been on death row since 1989 for the execution-style killings of three men in a southeastern San Diego auto shop. A survivor described the killings as a robbery. Ayala’s brother, Hector, was also convicted in the murders in a separate trial and sentenced to death. He appealed but the U.S. Supreme Court upheld his sentence in 2015.

The District Attorney’s Office did not list Ayala or Marquez among those charged as part of the takedown.

During the three-year investigation, correctional officers searched 39 prison cells and seized 23 cellphones, two SIM cards and meth. Four inmates were placed in administrative segregation as a result.


Authorities also seized six firearms, including an AK-47, during searches in other non-prison locations.

“This gang is extremely gruesome and calculated in their violence to inspire fear and intimidation,” said Summer Stephan, interim district attorney, in a statement.


kristina.davis@sduniontribune.com

Twitter: @kristinadavis