GUNNISON, Utah (ABC4) — The death of an inmate on Sept. 24 at the Central Utah Correctional Facility is now being investigated as a homicide, according to the State Bureau of Investigation.

Steven Davis, 66, was found unresponsive by prison staff on Sunday, Sept. 24. The manner of death has not been made public. Officials put the facility on lockdown as they started their investigation.

While officials have released very little information, they did confirm that investigators believe another inmate killed Davis. One of the inmates being investigated, according to the Utah Department of Corrections, had just arrived at the prison a few months ago after being convicted of murder.

Davis had been in prison since Dec. 1983, serving a sentence for first-degree sodomy of a child and parole violations.