Mexican national pleads guilty to brutal murder of Washington couple and unborn child

On Sept. 22, 2025, 22-year-old Benjamin Madrigal-Birrueta, a Mexican national in the US illegally and residing in Yakima, Washington, admitted in federal court that he executed 44-year-old Cesar Murillo on Aug. 28, 2022, during a dispute over a drug debt. Prosecutors said Madrigal-Birrueta shot Murillo multiple times in the head and torso, then ordered his body buried at a ranch outside Yakima.

Days later, Madrigal-Birrueta lured Murillo’s visibly pregnant wife, 33-year-old Maira Hernandez, to the same ranch. Unaware that her husband was already dead, Hernandez went with him only to be murdered execution-style by Madrigal-Birrueta’s co-conspirators. Her unborn child also died in the attack. Both victims were buried near the property.

The case began in 2021, when Homeland Security Investigations (HSI) seized narcotics at San Diego border crossings. Investigators eventually traced the drugs to Madrigal-Birrueta’s network in Yakima. Court filings show Murillo and Hernandez had been interviewed by federal agents just days before their murders.

After an exhaustive search effort involving radar, cadaver dogs, and forensic testing, HSI agents recovered the couple’s remains on Sept. 13, 2023. Authorities also seized firearms, body armor, and drugs tied to the criminal enterprise.

“This case underscores the commitment of HSI to pursue violent criminals who threaten our communities across state lines,” said HSI San Diego Special Agent in Charge Shawn Gibson. “Through the relentless work of our agents and the critical support of HSI Seattle, HSI Fresno, and our federal and local law enforcement partners, we were able to bring closure to a brutal crime and hold those responsible accountable.”

Madrigal-Birrueta is scheduled to be sentenced on March 27, 2026, and faces a lengthy prison term. His alleged accomplice, Ricardo Orizaba-Zendejas, has been charged as an accessory after the fact to murder and as a co-conspirator in the drug ring. Orizaba-Zendejas is slated to stand trial on Oct. 27, 2025.