LAS VEGAS (KLAS) — Four officers have been removed from their regular duties after the death of an inmate, the 8 News Now Investigators have learned.

Christian Walker, 44, died at High Desert State Prison on April 15. Officers used force against Walker with batons less than 48 hours before he was found unresponsive.

The four officers were placed on a no-contact order on April 17 pending the outcome of an investigation, according to the Nevada Department of Corrections. The officers will have minimal contact with offenders, they cannot respond to incidents, and they do not have access to weapons, a department spokesperson wrote in an email to the 8 News Now Investigators.

Walker had previously been housed at Southern Desert Correctional Center, a facility considered to house “medium custody” inmates. SDCC is located in Indian Springs, which is about a 45-minute drive north of Las Vegas.

Walker had run from officers at SDCC and was then transferred to High Desert State Prison on April 13, according to a department spokesperson. High Desert State Prison is a maximum security facility located near SDCC.

Officers reported that Walker did not comply during intake at High Desert State Prison. OC (Oleoresin Capsicum) spray, also referred to as pepper spray, was used to try to get Walker to comply and then several officers used batons, according to an internal document obtained by the 8 News Now Investigators. The same document stated that officers put Walker into mechanical restraints.

Several sources have told the 8 News Now Investigators that Walker was taken to a hospital and then returned to prison.

In this April 15, 2015, file photo, is High Desert State Prison in Indian Springs, Nev. (AP Photo/John Locher, File)

When Walker was found unresponsive on April 15, officers called 911 and CPR was administered until first responders arrived at the scene, according to the spokesperson.

The cause and manner of death were pending as of May 11, according to a spokesperson for the Clark County Coroner’s Office.

NDOC Director James Dzurenda requested an investigation by both the Nevada Attorney General’s Office and the Nevada Department of Public Safety.

“We are waiting for the investigation process to run its course and ensuring that the officers’ rights are protected,” Paul Lunkwitz, president of Fraternal Order of Police Nevada C.O. Lodge 21, the union which represents correctional officers, said.

Walker first went to prison in 1999 and was serving a sentence of 28 years to life with parole for second-degree murder, attempted murder, and two counts of use of a deadly weapon, according to the department.