Mexican Mafia Member Killed In Prison, RivCo Inmate Named As A Suspect

INLAND EMPIRE, CA — An inmate from Riverside County is a suspect in a condemned inmate's killing last week at Calipatria State Prison, authorities said.

Jorge D. Negrete-Larios, 33, is one of three inmates from the facility who allegedly attacked and killed Alberto Martinez, 46, at approximately 1:23 p.m. on Sept. 26.

According to the California Department of Corrections and Rehabilitation, prison staff witnessed inmate Tyler A. Lua strike Martinez, knocking him to the ground and continuing to hit him.

Lua stepped away, and inmates Negrete-Larios and Luis J. Beltran began attacking Martinez as he lay motionless in a prison yard, CDCR officials said.

Prison staff stopped the melee by using pepper spray and a baton strike on the three suspects, according to CDCR.

Two inmate-manufactured weapons were allegedly found at the attack scene.

Despite efforts to revive Martinez, he was pronounced dead about an hour after the alleged onslaught. He was most recently received from Orange County on Aug. 17, 2010, and placed on death row for first-degree murder. He was also sentenced to life with the possibility of parole for attempted first-degree murder with an enhancement for street gang activity and two years for street gang activity, to be served concurrent with the condemned sentence.

According to Los Angeles Times reporting, Martinez described himself in court as an associate of the Mexican Mafia. He was featured in a 2023 Times article detailing how members of the prison-based crime syndicate use smuggled cellphones to collect money and order murders.

Martinez was among death row inmates who were moved to the general prison population after Gov. Gavin Newsom imposed a moratorium on executions in 2019.

Negrete-Larios was received into state prison from Riverside County on July 5, 2016, after being sentenced to 32 years and four months for attempted second-degree murder with enhancements for inflicting great bodily injury, discharge of a firearm and street gang activity in commission of a violent felony.

Lua, 25, was received into state prison from San Bernardino County on Jan. 31, 2019, after being sentenced to 19 years for attempted second-degree murder with an enhancement for use of a firearm. While incarcerated, he was sentenced by Imperial County to two years for having a controlled substance in prison.

Beltran, 31, was received into state prison from Los Angeles County on April 6, 2023, after being sentenced to life without parole for first-degree murder with enhancements for intentional discharge of a firearm causing great bodily injury/death, and possessing/owning a firearm as a felon.

Lua, Negrete-Larios and Beltran were placed in restricted housing pending an investigation by the CAL Investigative Services Unit and the Imperial County District Attorney’s Office. The Imperial County coroner will determine Martinez’s official cause of death.

Calipatria State Prison in Imperial County houses approximately 2,638 minimum- and maximum-security inmates and employs approximately 1,200 people, according to CDCR.