by Todd Feurer, CBS Chicago web producer; CBS 2 Chicago staff contributed to this reportBy CBS 2 Chicago Staff

CHICAGO (CBS) — Mayor Lori Lightfoot on Monday said a “group of vigilantes” hijacked plans for a peaceful protest at the Christopher Columbus statue in Grant Park over the weekend, and police said 49 officers were injured when “organized mobs” pelted them with rocks, frozen water bottles, and explosives.

Monday morning, Chicago Police Department Area Three Deputy Chief Daniel O’Shea showed off video footage of a group of protesters forming a shield of umbrellas and changing into all-black clothing, before moving in “platoon-like fashion” with a barrier of banners connected by PVC pipe, before throwing frozen water bottles, rocks, and fireworks at officers guarding the statue on Friday evening.

Police said some of the PVC pipe holding the banners together also had been sharpened at the ends, and some protesters used the pipes to jab at police officers.

O’Shea said there had been multiple peaceful protests at the statue in past few weeks, but he called what happened on Friday “an ambush on police officers.” He said there were groups of people pushing carts and carrying bags with weapons to throw at police.

Police Supt. David Brown denounced what he called “organized actions to provoke violent responses from our officers.”

“Peaceful demonstrations have been hijacked by organized mobs. Yet, in the face of this action to provoke a violent response, the vast majority of officers have been professional, and have exhibited great restraint,” he said.

The superintendent said 49 officers were injured during Friday’s protest at the Columbus statue, including 18 who were sent to hospitals for their injuries. Brown said one sergeant suffered a broken eye socket when an explosive was thrown toward police, detonating near his face. O’Shea said that sergeant might need surgery for his injuries.

Lightfoot said while people have a “sacred right” to peacefully protest in the United States, and she said she supported what had been planned as a “to really uplift the stories of indigenous people here in Chicago” on Friday evening in Grant Park. Unfortunately, she said those plans were hijacked by “a group of vigilantes.”

“People who came for a fight, not a peaceful protest,” she said. “You’re going to see video that shows these people, before they got to the Columbus statue, kneeling down, dressing in all black, with goggles, forming a phalanx with umbrellas, and with shields around them, and then pummeling the police with projectiles; frozen water bottles, cans, other projectiles.”

“That’s not peaceful protest, that’s anarchy, and we are going to put that down. We are actively investigating, and we will bring those people to justice,” she said.

However, the mayor also said she was “not happy about some of the things that I saw with people who were injured” by police officers during the protest.

“I’m not happy and don’t support interfering with reporters doing their job. So if that has happened, I urge anyone who believes that they were mistreated at the hands of the police to call 311 and otherwise report it to COPA (the Civilian Office of Police Accountability),” the mayor said.

COPA said Sunday that it had received more than 20 complaints against Chicago Police officers as a result of protests in Grant Park. The complaints included claims of excessive force, unnecessary oleoresin capsaicin (OC) spray or pepper spray, denial of counsel, and operational violations.

Miracle Boyd, 18, said she had at least one tooth knocked out by a Chicago Police officer during the unrest on Friday. Some friends believe the officer was trying to punch away her phone and instead hit her in the mouth.

Video shows Boyd getting punched in the mouth by a Chicago Police officer – hard enough to lose at least one tooth while shooting video on her phone.

“There was no way I should have left a protest bruised and battered for exercising my freedom of speech, and freedom to assemble. I am disgusted and never would have ever thought I’d become a victim to the biggest gang in America,” Boyd said Monday.

Lightfoot said COPA will do their job to investigate what happened.

Brown said the Chicago Police Department also would investigate any allegations of misconduct.

“We will conduct a thorough investigation of any and all allegations, and take the appropriate action,” he said.

Police said there were 12 arrests made during Friday’s protest; for mob action, battery to a police officer, and criminal damage to property, after several protesters tried to tear down the Columbus statue.

Brown said toppling the statue could have caused serious injuries or death to those in the crowd.

“This cannot stand. We cannot be a city that thinks mob action of a crowd is acceptable behavior. When mob action occurs, CPD is forced to divert our manpower away from deterring violent crime in our neighborhoods, in order to quell the unrest,” he said.

The superintendent also said CPD would have to change its tactics for responding to peaceful protests in the future, to be prepared for protests to potentially turn violent.

“We’ll have to change the way we deploy our resources, how we’re trained,” he said. “We have to assume the best, but also prepare for the worst.”

Brown said he is ordering officers to wear full protective gear whenever protests occur.

“We must protect our officers. We cannot assume that protests are going to be peaceful, based on these actions and others,” he said. “We must protect our officers from this kind of violence from these mobs.”

Last month, Lightfoot said statues of Columbus in Chicago should not be torn down, but instead should instead be used to teach young people about the nation’s full history.

In the wake of Friday’s protest in Grant Park, the mayor said her office this week will announce a process to take stock of the city’s monuments, and determine which ones need to change.

“We need to also understand what isn’t there. I believe that it’s true, and our team will determine, there are no monuments to African Americans in this city. There are no monuments to women. There are no monuments that reflect the contributions of people in the city of Chicago who contributed to the greatness of this city, and we need to correct that problem,” she said. “It’s not about a single statue, it’s about how we want to reflect our values as a city to make sure that everyone is reflected in our history, and particularly in our permanent memorialization of artistry. We have not historically done that. We need to do that, and this is the moment to address it.”