US police officer punches woman in the face during arrest

An Arizona police officer has been captured punching a woman in the face during an arrest.

Seven minutes of mobile phone footage captures the unconventional arrest on Wednesday.

In the video, the woman can be heard arguing that she knows her rights and could not legally be arrested.

"I know my laws," the woman can be heard saying.

"You can’t arrest me until I know that I have a warrant."

Officer Jeff Bonar can be heard repeatedly telling the woman to "stop resisting".

Failing to head Officer Bonar's warning, he strikes her in the face with an open fist.

"You can’t hit her like that," a bystander can be heard yelling.

The police officer then threatens to tase the woman if she doesn't sit on the ground.

The Flagstaff Police Department said they are aware of the footage and an investigation into Officer Bonar's actions is underway.

He has been placed on paid administrative leave, pending the investigation's outcome.