Alberto Martinez Villarino, 43, died on June 7, 2016, while incarcerated at Calipatria State Prison in Imperial County, California. The Los Angeles County Medical Examiner‑Coroner classified his death as a homicide. Prison staff observed fellow inmates attack Martinez; records state Tyler A. Lua struck him and knocked him to the ground, then Jorge D. Negrete‑Larios and Luis J. Beltran beat him as he lay motionless. Martinez died of injuries consistent with an incarcerated‑manufactured weapon and was pronounced dead at the prison’s triage and treatment area.

Martinez had been on death row since August 17, 2010, after conviction for first‑degree murder, attempted first‑degree murder with a street‑gang enhancement, and conspiracy for his role as the getaway driver in the kidnapping and murder of businessman David Montemayor. The three inmates were moved to restricted housing pending investigation. No motive has been disclosed and no staff or other inmates were reported injured.

Did anyone with knowledge of Calipatria or these inmates notice tensions or incidents before June 7, 2016?