SACRAMENTO (AP) — One inmate died and two others were seriously injured in a fight Monday that involved about 40 inmates at a state prison in the San Joaquin Valley, corrections officials said.

It was one of two inmate deaths reported Monday in apparently unrelated incidents.

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A guard fired one bullet to quell the fighting that broke out at about 9:20 a.m. in an exercise yard at Wasco State Prison, said Lt. Floyd Harl, a prison spokesman.

Three inmates were taken to Delano Regional Medical Center, and 22-year-old Angel Torres was pronounced dead at 10:13 a.m., according to the Kern County coroner’s office.

Torres was serving an 11-year sentence for an assault with a deadly weapon conviction in Riverside County, Harl said. Torres arrived at the prison from Riverside on March 12.

The cause of Torres’ death has not been determined, Harl said. The coroner’s office said an autopsy would be performed Tuesday.

Harl said it was not immediately known if the guard’s bullet caused any of the injuries, if any weapons made by inmates had been recovered, or if correctional officers used tear gas or other weapons beyond firing a shot to break up the fight.

“We’re still collecting all the information,” he said. “They’re trying to put it together.”

No employees were injured.

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Harl said he did not know what set off the fighting at the prison, which houses about 5,000 inmates in six housing units. Inmates in the housing unit where the fight occurred were locked in their cells as the investigation continued.

All the inmates involved in the fight were of the same ethnic background, Harl said, and it was not immediately clear if the fight was gang-related.

The prison is located about 260 miles south of the state capital. It generally houses inmates who are just beginning to serve their sentences and evaluates new inmates before they are sent to other prisons to serve their time.

Also Monday, authorities said they were investigating the death of a 48-year-old inmate at a state prison in Lancaster as a homicide.

Bill Sessa, a spokesman for the California Department of Corrections and Rehabilitation, said Victor Jones’ death Friday at California State Prison-Los Angeles County was originally thought to be the result of natural causes.

Jones was found dead on a housing unit dayroom floor, and officials now believe he was fatally beaten.

The death is now classified as a homicide and another inmate is being held as a suspect, Sessa said. The Los Angeles County Sheriff’s Department was investigating.

Jones was serving a life sentence for a Riverside County robbery at California State Prison-Los Angeles County. The facility holds more than 3,700 inmates.

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