This is the moment a Phoenix cop apparently punches a heavyset 13-year-old girl while placing her under arrest.

The Phoenix Police Department shared the body-cam footage on social media on Tuesday, 1st February, after eyewitnesses posted clips on social media that drew outrage from many netizens.

The police said officers were responding to reports of a resident following their stolen car on the streets at around 4.30pm on Monday.

The police then located the allegedly stolen car at an apartment complex a short while later.

The police moved in when they saw four men getting out of the vehicle, but were quickly surrounded by a group of people filming the incident.

While telling the mob to back off, one of the suspects, named as Javon Johnson, 25, allegedly punched a cop in the face and grabbed hold of his firearm, according to the police.

The 13-year-old girl approached the police while they were arresting people and officers told her to back off multiple times.

She allegedly tried to intervene while one man was being put in a patrol car, and a female officer grabbed her arm and went to place her under arrest.

The police said the girl hit the officer in the face and knocked off her body camera.

The cop allegedly responded by hitting the teenager in the face before forcing her on the ground to detain her for assaulting an officer.

The 13-year-old girl was later booked into a juvenile court for aggravated assault on a law enforcement officer.

Meanwhile, the Phoenix police said the incident is still under review.