Three police officers and a sergeant in Mesa, Ariz., have been placed on leave after the police chief was shown surveillance video footage of multiple officers surrounding an unarmed black man and punching him repeatedly.

The beating has prompted protests in Mesa, a suburb of Phoenix.

Chief Ramon Batista told the media that he was not aware of the incident until a member of the community informed him. He released the footage publicly, in the name of transparency.

"It is important for me to convey to our community that their trust in us is paramount, and that's why I want to be transparent in talking about it," Batista told Fox 10. "This is not unnoticed. This is going to be investigated."

The man in the video, which was recorded May 23, has been identified as Robert Johnson. At the time police began to hit him, he had already been patted down for weapons and was standing against a wall looking at his phone.

The video shows multiple police officers surrounding him, kneeing him and punching him until he falls to the ground, while other officers watch. One officer can be clearly seen punching Johnson in the face repeatedly.

Police released the surveillance footage on Tuesday. The Mesa Police Association criticized the release of the video, calling it "grossly inappropriate" to release video before the internal investigation was complete.

The surveillance footage does not include audio, but on Wednesday, police also released body camera footage, which does have audio. One of the recordings shows officers telling Johnson to "have a seat." Johnson leans against the wall and slides down, moving his feet forward. "All the way down," police say, before the officers move in and begin to strike. You can hear one officer repeating, "See what happens?" shortly after.

"You didn't need to put all that force on me," Johnson says afterward. "Did it feel good, putting your hands on me while I was subdued?"

He curses loudly and laughs at the police; one officer tells him he is "disturbing the neighbors." At one point, Johnson tells the police they were using excessive force, and an officer repeatedly corrects his pronunciation of "excessive." The body cam footage also shows an officer accusing Johnson of trying to spit at him — which Johnson denies — and then pushing Johnson's face into an elevator.

Police say they were responding to call from a woman who reported that her ex-boyfriend was trying to break into her apartment. Johnson was accompanying the ex-boyfriend, who said he was trying to get a backpack from the apartment.

After the police punched him and handcuffed him, Johnson was arrested for disorderly conduct. The three officers and a sergeant were placed on leave after the surveillance video surfaced.

Johnson's attorney, Benjamin Taylor, tells The Associated Press that the officers should be suspended and disciplined. He also told the news service that he wants the charges against Johnson to be dropped.

The Arizona Republic reports that the Mesa Police Department has been criticized over officers' use of force previously:

"In February, the family of an 84-year-old grandmother posted pictures of a woman's bruises after a Mesa police officer grabbed her and took her down. After the pictures went viral on Facebook, Mesa police video showed the takedown. Police had originally said the woman slipped.

"In December, after former Mesa police Officer [Philip] Brailsford was acquitted by a jury of a second-degree murder charge, a judge allowed the release of unedited footage showing Brailsford fatally shooting a man who was on his knees crying, begging for his life. In that video, taken from police body cameras, a sergeant can be heard yelling commands at the man.

"The incident happened in January 2016, but the unedited video was released almost two years later, prompting international outcry on social media."

Editor's note: The spelling of Sgt. Philip Brailsford's name has been changed because it had been spelled incorrectly in quoted material from theArizona Republic.

Copyright 2021 NPR. To see more, visit https://www.npr.org.