(KRON) -- An inmate who was convicted of murder in Contra Costa County recently attacked two prison guards, California Department of Corrections and Rehabilitation officials said. Ronald D. Yandell, 62, was being escorted to his cell inside California State Prison Sacramento when he allegedly pulled out an improvised weapon on November 22. CDCR officials said Yandell attempted to kill two guards with the weapon. "One of the officers deployed three applications of pepper spray. Yandell dropped theimprovised weapon (and) was placed in restraints," a CDCR spokesperson wrote. Ronald Yandell's 2022 prison mugshot was released by the CDCR. Yandell has been locked up for two decades. He is serving a life sentence with possibility of parole for first-degree murder. He's now facing new charges, attempted homicide, for the November 22 incident. The case was referred to the Sacramento County District Attorney’s Office for felony prosecution.