Wasco State Prison officials are investigating the death of an inmate as a homicide.

On Saturday night, officials say 19-year-old inmate Andres Ayon began striking 66-year-old inmate Agustin Duran with his fists in the face and upper body. An alarm was sounded and all inmates got to the ground, except for Ayon, who continued to hit Duran.

Staff used a pepper spray grenade to get Ayon to comply; he was transported to a temporary holding cell. Meanwhile, Duran was airlifted to a hospital and declared dead the next day.

Duran was in prison serving 55 years to life with the possibility of parole for lewd and lascivious acts with a child under 14.

Ayon has been placed in the Administrative Segregation Unit while the incident is investigated, and is serving six years for second-degree robbery and use of a weapon.