A mentally ill man was caught on video being viciously pummeled by a prison guard who switched off his body cam before the beating began.

In the March incident, Terrance Debose, 47, was tied to a chair in a Cuyahoga County Jail cell in Cleveland, Ohio, when Corrections Cpl. Nicholas Evans started beating the restrained man.

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A surveillance camera was rolling the moment Evans touched his chest in a manner that appeared to show him turning his body camera off, before the prisoner took multiple face and body shots, The Cleveland Plain Dealer reports.

Debose was left defenseless as he endured the attacked for about 13 seconds. Another corrections officer, Timothy Dugan, also punched Debose before the video ended.

The guards then left Debose bleeding while strapped to a chair for another two hours.

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Evans was charged with felonious assault and Dugan was charged with misdemeanor assault. Both officers are also charged with being in violation of Debose’s civil rights. The officers have pled not guilty. Evans could serve eight-years in prison if he’s found guilty of the brutal attack.

Debose is still housed in Cuyahoga County jail on cocaine possession and evidence tampering charges.

His brother, Emanuel, said that family wants justice.

“I want justice for him,” he told the Plain Dealer. “They don’t have the right to do that. You see so much police brutality. I just want justice served at this point.”

“He said they beat him up bad,” Emanuel said about what Debose told him after the attack. “He said he wasn’t really able to talk because they’re recording the calls from the jail. He asked if I could get him some help, but I really didn’t know how to go about doing that type of stuff.”