A man from Los Angeles County was killed inside his cell at California State Prison, Sacramento in Folsom while serving a 33-year sentence for robbery and sex crimes, state authorities announced Wednesday.
Officials with the California Department of Corrections and Rehabilitation said John Cisneros, 49, was found unresponsive inside his cell at around 9:15 p.m. on Monday.
An outside medical ambulance was called in, but Cisnero was pronounced dead at around 10 p.m. by the ambulance staff.
Cisnero was incarcerated in July 2015 after being convicted of second-degree robbery as well as penetration, oral copulation and attempted rape with force/violence/fear of immediate bodily injury.
Investigators believe Cisnero was killed by his cellmate, Irvin Sanchez, who has since been placed in restricted housing.
Sanchez has been serving an 18-year-sentence since 2013 for attempted second-degree murder with enhancements of street gang act and use of a firearm, officials said.
The Folsom prison is a medium to high-security facility, housing more than 2,200 inmates with about 1,500 employees, state officials said.