(CNN) — Thirteen Chicago police officers lounged and slept in the congressional campaign office of US Rep. Bobby Rush on June 1 as protests and demonstrations occurred throughout the city, Rush and Chicago Mayor Lori Lightfoot said Thursday.

The officers, who included three supervisors, were seen on video lounging in Rush’s office, sleeping, eating the congressman’s popcorn and talking on the phone, Rush and Lightfoot said.

The incident came to light after Rush reviewed security camera footage from his office, the mayor explained at a news conference. It’s not clear who broke into the office.

“They even had your unmitigated gall to go and make coffee for themselves and to pop popcorn — my popcorn — in my microwave,” Rush said.

“They did not care what was happening to business people in this city,” Rush added.

“I can tell you one thing for certain — not one of these officers will be allowed to hide behind the badge and go on and act like nothing ever happened,” Lightfoot said. “Not anymore. Not in my city, not in your city.”

The security video picks up around 1 a.m. on June 1 and shows the officers were in the office for at least five hours, Lightfoot said.

There was a core group of eight officers, but at one point the group grew to as many as 13, the mayor added.

Protests were taking place in Chicago in the wake of the death in custody of George Floyd in Minneapolis a week earlier.

Later on June 1, Lightfoot held a news conference describing attacks on local storefronts and businesses that were “nothing short of devastating.”

The city’s 911 operators had received 65,000 calls in a 24-hour period, about 50,000 more than what the city sees on a typical day, Lightfoot said.

A day earlier, on May 31, Lightfoot said there was violence in the city, including looting.

Thursday, Chicago police Superintendent David Brown condemned the officers’ actions in the surveillance video.

“If you sleep during a riot, what do you do during a regular shift when there is no riot?” Brown said.

“Step up, or step out. I’m not playing,” he added.

First Deputy Superintendent Anthony Riccio called the actions “completely indefensible.”

Lightfoot said they are working to identify the officers involved.

“You know who you are. Don’t make us come find you. We will find you,” she added.

CNN has reached out to the union but has not received a response.

Lightfoot said she wanted “the strongest possible action” to be taken against the officers involved and noted that the state’s attorney and US attorney will review the case as well.

She also said she wants to use the incident to pass police reform legislation.

“I am ready to work with the governor, and our other great partners in Springfield, to forge a change in state law to require licensing and certification of police officers,” Lightfoot said.

The-CNN-Wire™ & © 2024 Cable News Network, Inc., a Time Warner Company. All rights reserved.

Join our Newsletter for the latest news right to your inbox