BOSTON (CBS) – An internal investigation is underway at the Boston Police Department after body camera footage was released from the night protests broke out in Boston over the killing of George Floyd. One sergeant has been placed on administrative leave during the investigation.

Thousands of demonstrators took to downtown streets on May 31 calling for racial justice after the death of Floyd in Minneapolis. The website TheAppeal.org released a few short video clips from hours of police body camera footage from that night.

An attorney representing some of the protesters arrested requested the video.

In one clip, a police officer is heard telling a fellow officer about driving his cruiser down Tremont Street and hitting people.

On the video, the second officer realizes his camera is rolling and walks away. When he returns, the officer said he didn’t hit anyone but his cruiser was struck by protesters.

Boston Police Commissioner William Gross said he immediately ordered an investigation as soon as the videos were brought to his attention.

“I have placed a Sergeant involved in this incident on administrative leave and I will take any additional action as necessary at the conclusion of the investigation,” Gross said in a statement. “I want to encourage people to bring these matters to our attention so that we can investigate them appropriately.”

Boston Mayor Marty Walsh said the city is implementing body cameras for all police officers because of situations like this.

“This footage is difficult to watch, and begs answers to many questions that I expect to be answered through an Internal Affairs investigation,” Boston Mayor Marty Walsh said in a statement. “We never want to see police officers using more force than necessary, even when tensions are high.”

A spokesperson for Suffolk County District Attorney Rachael Rollins said she is aware of the video and is investigating.

It was a violent night in the city and 53 people were arrested. The National Guard was called in as protesters looted stores, set fires and destroyed police vehicles from Downtown Crossing to Newbury and Boylston streets.