Injuries resulting from blunt force trauma led to the death of California Men’s Colony inmate Michael Walsh, who was killed Saturday during an altercation with another inmate.

Walsh died from brain swelling due to a hemorrhage caused by blunt force trauma to the head, according to autopsy results released Thursday. The coroner also found Walsh inhaled blood from blunt force trauma to his face, which contributed to his death.

The prison’s investigative services unit is in charge of the ongoing homicide investigation.

Prison officials said Monday that they have identified a suspect who is being held in the administrative segregation unit. Charges have not yet been filed with the San Luis Obispo County District Attorney’s Office.

A correctional officer found Walsh, 51, in the dining room lying face down, motionless and unresponsive.

Walsh had been incarcerated at the prison since June 30, 1997, and was serving a life sentence for multiple charges, including assault with a deadly weapon on a peace officer, false imprisonment, sexual assault with force and assault with a deadly weapon.