(CNN) — A Minnesota mayor on Wednesday called for criminal charges against the police officer who pinned George Floyd to the ground with his knee shortly before Floyd’s death — a videotaped incident that spurred street protests and local and federal investigations.

“What I can say with certainty, based on what I saw, is that … the officer who had his knee on the neck of George Floyd should be charged,” Minneapolis Mayor Jacob Frey said in a news conference.

Frey declined to say what the officer should be charged with, and said his knowledge of the evidence is “limited to the video evidence that is there.” He said he’s made his opinion known to Hennepin County Attorney Mike Freeman, whose office would be in position to file state charges.

“George Floyd deserves justice. His family deserves justice. The black community deserves justice, and our city deserves justice,” Frey said.

No charges have been filed in the case.

Floyd, a black man, was arrested Monday evening after officers responded to a call about an alleged forgery in progress.

Video from bystanders shows Floyd handcuffed and pinned to the ground and one police officer’s knee pressing against his neck. Floyd says that he is in pain and can’t breathe. He was declared dead at a nearby hospital shortly afterwards.

Four police officers involved in the incident were fired Tuesday, Minneapolis police said. That includes Officer Derek Chauvin, the officer seen on video restraining Floyd with his knee, Chauvin’s attorney Tom Kelly said.

Kelly said he wouldn’t yet release a statement on Chauvin’s behalf.

A finding on the cause and manner of Floyd’s death is pending and it is being investigated by local, state and federal law enforcement, the Hennepin County Medical Examiner’s Office said.

Frey’s comments came a day after hundreds of people protested Floyd’s death in Minneapolis’ streets, starting at the intersection where Floyd was arrested and moving to a police precinct.

Some demonstrators on Tuesday chanted “No justice, no peace” — as well as “I can’t breathe,” which were some of the last words Floyd uttered Monday in the bystander video.

“We’re here to let them know this can’t be tolerated, there will be severe consequences if they continue to kill us. This will not go on another day,” a protester told CNN affiliate WCCO.

An attorney representing Floyd’s family, Benjamin Crump, said in a statement Wednesday that he and Floyd’s relatives are calling for peaceful protests and social distancing amid the coronavirus pandemic.

“We cannot sink to the level of our oppressors, and we must not endanger others during this pandemic,” the statement said. “We will demand and ultimately force lasting change by shining a light on treatment that is horrific and unacceptable and by winning justice.”

Tear gas used after crowd turned unruly, police say

Police used tear gas to disperse a crowd Tuesday after some protesters turned unruly, Minneapolis police spokesman John Elder told CNN.

Officers outside Minneapolis Police Department’s 3rd Precinct fired what appeared to CNN’s team on the scene to be non-lethal projectiles at demonstrators.

The officers fired “foam marking rounds,” but no rubber bullets, Elder said.

Those rounds are meant to mark individuals that officers believe may be instigating violence for later investigation, Elder said.

Family: Officers should be charged with murder

 Members of Floyd’s family say they want four officers at the scene charged with murder.

“They were supposed to be there to serve and to protect and I didn’t see a single one of them lift a finger to do anything to help while he was begging for his life. Not one of them tried to do anything to help him,” Tera Brown, Floyd’s cousin, told CNN’s Don Lemon on Tuesday.

Brown and Floyd’s two brothers held up his picture during Tuesday’s interview and spoke of a man who “didn’t hurt anybody” and who they described as a “gentle giant.”

“Knowing my brother is to love my brother,” Philonise Floyd said. “They could have tased him; they could have maced him. Instead, they put their knee in his neck and just sat on him and then carried on.”

“They treated him worse than they treat animals,” he said.

“They need to be charged with murder because what they did was murder,” Brown said. “And almost the whole world has witnessed that because somebody was gracious enough to record it.”

“They need to pay for what they did,” she said.

‘I can’t breathe’ 

Minneapolis police said officers were responding to a report of a forgery Monday evening and were told a person later described as the suspect was sitting on a car.

They found Floyd, who at that point was inside a car and police said he “physically resisted” after he got out of the vehicle. Officers handcuffed Floyd, who police said “appeared to be suffering medical distress.”

Video captured by bystanders shows Chauvin with his knee pressed against the neck of the 46-year-old, who was handcuffed on the pavement. Two officers handled the man on the ground while another stood nearby with his eyes on the bystanders as traffic passed.

“Please, I can’t breathe,” Floyd says. “… My stomach hurts. My neck hurts. Everything hurts.”

At one point the Floyd said, “Give me some water or something. Please. Please.”

Surveillance video obtained from a nearby restaurant showed the first point of contact police had with the man. An officer escorts Floyd handcuffed out of a car and Floyd sits on the sidewalk. Moments later, the officer and another escort Floyd away, still with his hands behind his back.

Officers’ attorneys had represented other Minnesota officers in high-profile deaths

The Police Officers Federation of Minneapolis said Tuesday the four officers were cooperating in an investigation and urged “now is not the time to rush to (judgment)” while the officers’ actions are examined.

At least three of the fired officers are being represented by attorneys who previously represented other police officers involved in high-profile killings in Minnesota.

Chauvin’s attorney, Kelly, represented then-St. Anthony police Officer Jeronimo Yanez, who shot and killed Philando Castile during a traffic stop in Falcon Heights in July 2016. A jury found Yanez not guilty of manslaughter; Castile’s family and his girlfriend reached settlements with various cities.

Attorneys Earl Gray and Thomas Plunkett also are representing officers involved in Monday’s incident — but they are not naming their clients.

Gray, like Kelly, had represented Yanez.

Plunkett was involved in the defense of Minneapolis police Officer Mohamed Noor, who was convicted of third-degree murder and manslaughter for shooting and killing Justine Ruszczyk while responding to her 911 call in July 2017.

FBI investigating

The Federal Bureau of Investigation has opened an investigation into Floyd’s death, which will focus on whether the Minneapolis Police Department officers involved “willfully deprived (Floyd) of a right or privilege protected by the Constitution or laws of the United States,” according to a statement from the FBI Minneapolis Division.

The FBI said it will present its findings to the United States Attorney’s Office for the District of Minnesota for consideration of possible federal charges.

Monday’s incident recalls the 2014 death of Eric Garner, who also uttered the words “I can’t breathe” while in a New York officer’s chokehold. Since Garner’s death, the phrase has become a rallying cry throughout the Black Lives Matter movement.

That officer never faced charges. He was fired in 2019 after being found guilty in a disciplinary trial of using a chokehold on Garner and later sued the city over his termination.

On Wednesday Garner’s mother told CNN that Floyd’s death feels like déjà vu.

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