iStock/Thinkstock(DETROIT) — A Detroit police officer is the subject of a criminal investigation after a “disturbing” cell-phone video surfaced showing him repeatedly punching an apparently emotionally disturbed naked woman at a hospital, officials said Thursday.

Detroit Police Chief James Craig announced at a press conference that the officer, an 18-year veteran of the police force, has been suspended after he was seen in the video beating the woman even after she had turned her back to him and was trying to retreat.

Craig said the incident happened on Wednesday at Detroit Receiving Hospital and that the victim, whose name was not released, suffered minor injuries.

A witness took the cell-phone video of the incident, which was later aired by Fox affiliate station WJBK-TV in Detroit. Craig said the video was turned over to police about 8:30 p.m. Wednesday.

“It’s very disturbing,” Craig said. “However, I want to remind everyone that we have initiated and started a criminal investigation, but the officer is entitled to due process.”

In the video, the woman is completely nude and seen struggling with police and security guards at the hospital. The police officer, whose name was not released, is seen repeatedly punching the woman with his fists in her head and body.

Craig said he has compared the video to the body-worn camera footage from the officer and his partner, saying “it tells a little bit of a different story.”

“Certainly the suspect, in this case, became very agitated,” Craig said. “She was threatening, clenched fists. She spat on several of the hospital employees. In addition to that, a member of the security staff was bitten twice and sustained injury.”

“At some point, she tried to bite the officer who used force,” Craig said. “So as he was trying to calm her down, at some point, the officer began to strike her because she wasn’t responding, she was not compliant.”

He said the officer and his partner first encountered the woman after answering a call about 6:45 p.m. of a “lewd and lascivious” act in progress.

“When the officers got to the location they were in contact with a lone female who was not clothed,” the chief said. “She was passive, she didn’t appear to be agitated and the officer knew that she was more than likely in a mental crisis.”

Craig said the officers covered the woman with a robe and drove her to Detroit Receiving Hospital.

He said one of his “concerns” is that the officer did not handcuff the woman, which is not in keeping with department training.

“We know from our training and experience that anytime we transport someone, particularly if they’re suffering from mental illness, for their safety, for the officers’ safety and for the community’s safety that we handcuff,” Craig said. “Once she gets into the hospital, though, she takes off the robe and that’s when things begin to change.”

He noted that there were points in the video “where the suspect had turned her back but the officer continued to punch. It was at that point we had grave concerns for the officer’s actions…”

The officer has been placed on paid administrative leave and that the Wayne County District Attorney’s Office is conducting the criminal investigation, Craig said.

He said the officer is a corporal, who has not had a complaint lodged against him since 2015. The officer has had six “minor uses of force” in his 18-year tenure with the force, but this is his first “category 1” use of force incident, meaning an injury occurred as a result of his actions, Craig said.

He said the officer has attended mental health and emotional survival training, twice in 2016 and once in 2015.

“At this point, I can’t tell you why the officer didn’t opt for using a Taser, why he didn’t wait for backup,” Craig said. “Those are the things that we’ll be determining throughout this investigation.”

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