A police officer seen on video striking a woman in the face during an arrest is now on leave, police in Arizona confirmed Wednesday.

WARNING: VIDEO CONTAINS GRAPHIC LANGUAGE

Officer Jeff Bonar was detaining the woman Wednesday because he knew about warrants for Marissa Morris' arrest, Flagstaff Police Chief Kevin Treadway said. He added that police determined the warrants were no longer active.

Investigators had described the woman as "somewhat uncooperative." The officer claimed she kicked him and kneed him in the groin before he hit her, the police chief added.

Her boyfriend reportedly recorded the video before it appeared on Facebook, according to Fox 10.

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Police eventually placed the woman in a squad car.

The department was conducting an internal affairs investigation and asking the Northern Arizona University Police Department to conduct a criminal investigation, Treadway said.

"Our agency is very concerned by what is depicted in this video," Flagstaff Police said in a news release.

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The Associated Press contributed to this report.