Footage shows mentally ill prisoner 'viciously' attacking four guards in psychiatric ward of Arizona jail

One of the officers was injured so badly he will now require facial reconstruction surgery

The man attacked four guards before being restrained by the guards (Maricopa Sheriff County)

This is the moment a “mentally ill” man brutally attacked four prison guards at an Arizona jail, leaving one hospitalized with severe facial injuries and bleeding on the brain.

The 18-year-old inmate had been incarcerated in the mental health unit of the Lower Buckeye jail in Phoenix for two weeks when he carried out the attack on the jail employees.

The incident happened when officers spotted the unnamed 18-year-old inmate walking in a section of the prison he was not authorised to be in.

After approaching the inmate to tell him to return to his cell, guards say the man turned on them punching one of the guards three times in the face before attacking the other guard.

One of the officers, 15-year-old veteran Scott Beaty was beaten so badly by the inmate that he had to be sent to intensive care and will now require reconstructive surgery on his face.

More officers eventually arrived to subdue the man, but not before the inmate assaulted two more officers.

According to those at the prison, the 18-year-old inmate who was arrested on a minor felony charge had never shown any signs of violent behaviour before.

Speaking at a press conference after the incident, Maricopa County Sheriff Joe Arpaio said:

"Our guys tried to do the best that they could," Arpaio said. "They used a Taser, but that did not have much effect on the 18 year old.

"We never know what is going to happen in jail, especially in the psychiatric ward"

The inmate is now said to be “locked down” in his cell for 23 hours a day and will face charges of aggravated assault that may see his sentence extended.