PHOENIX -- The Maricopa County Sheriff's Office accused CBS 5 News on Wednesday of altering video and distorting the truth in a 5 Investigates probe of a jailhouse death.

Watch: Uncut MCSO Press Conference Regarding Jail Death

In an afternoon news briefing, MCSO Chief of Custody Jerry Sheridan took aim at a CBS 5 News investigation and said that the death of Robert Cotton, who was beaten and strangled to death by another inmate in a Maricopa County jail, could not have been prevented.

"That video shown on Channel 5 was technically enhanced and does not accurately reflect what any detention officer could have observed on the night of the murder," Sheridan said.

CBS 5 News Director Michelle Donaldson said the station stands by its investigation.

"At times during our report, we isolated or zoomed in on the surveillance video," she said. "However, everything on that video is as it happened in the jail and as it was recorded by the surveillance cameras."

READ: Statement From CBS 5 On Investigation Of Jail Death

On May 1, inmate Pete Van Winkle attacked Cotton -- beating, strangling and jumping on the victim's head for nearly 20 minutes, surveillance footage shows.

Detention officers said once they spotted Van Winkle dragging Cotton out of his cell, they rushed to the scene within seconds; the footage, however, shows it took the guards an additional five minutes to reach Van Winkle.

"It took three and a half minutes, not five as reported, for a team of detention officers to safely respond to a dangerous situation inside the housing unit," Sheridan said at Wednesday's news briefing. "Cameras in the housing unit captured portions of the incident. But cCannel 5 manipulated the video to lead their viewers to believe the detention officer could zoom into the incident, and the murder was in full view of the officer."

5 Investigates discovered the guard who was supposed to be monitoring the security cameras was talking on the telephone at the time.

• READ: Video Contradicts MCSO's Version Of Jail Slaying | WATCH: Video Shows Man Slain In MCSO Jail

The slaying appears to have been a "hit" ordered by the Aryan Brotherhood against Cotton because Cotton refused to beat up another inmate, according to the official incident report prepared by the Maricopa County Sheriff's Office.

Van Winkle has been charged with first-degree murder, and he is facing the death penalty. Officials have not charged anyone else in connection with the death.