While police leaders join protesters in denouncing the death of George Floyd, those behind the violence in cities across the country are getting more diverse.
Floyd, 46, died one week ago after a Minneapolis officer pressed his knee on Floyd's neck for 8 minutes, 46 seconds. His final words included "Mama" and "I can't breathe."
Outrage and protests spread rapidly from coast to coast -- not just over Floyd's death, but also those of other unarmed black men in police custody.
Most protesters have been peaceful, with people carrying "Black Lives Matter" and "I can't breathe" signs.
But some have turned violent, torching buildings, destroying police cars, smashing windows and looting stores. Federal law enforcement officials said groups including white supremacists and anarchists have fueled the violence.
About 4,000 people have been arrested across the country since Tuesday, according to CNN's tally from officials nationwide.
There have been aggressive actions by officers, too. In New York City, a police vehicle was seen plowing through a crowd of protesters. In Atlanta, two officers were fired after their violent arrest of two college students was caught on video.
And dozens of officers across the country have been injured by rocks or other objects hurled at them.
"We have officers with broken bones and bruises," Chicago Police Superintendent David Brown said Sunday. "More than 20 officers went to the hospital. At least two of these required surgery."
The former officer who pinned Floyd to the ground, Derek Chauvin, was initially expected in court Monday. But that appearance has been rescheduled for June 8.
Chauvin is charged with third-degree murder and second-degree manslaughter. If convicted, he faces up to 25 years in prison on the murder charge and up to 10 years on the manslaughter charge.
But those charges aren't enough to quell protests across the country. Many activists say they want charges for the three other officers who were near Chauvin but did not intervene.
In Atlanta, protester Michelle Sheffield wore a face mask with the words "I can't breathe" -- a mask she actually made after the death of Eric Garner, who died in 2014 after a New York City police officer wrapped his arm around Garner's neck.
She said it's disappointing that six years later, she's protesting again. And she's upset that agitators have sparked violence.
"If my kid can't go to the store and (safely) get me a gallon of milk, then what's the point? We're fighting a losing battle," Sheffield said. "It has to stop somewhere, and it has to stop with us."
23 states have activated the National Guard
More than 17,000 National Guard members across the country are responding to civil disturbances in support of local authorities, a National Guard official said Monday.
At least 23 states and the District of Columbia have activated guard members.
In Long Beach, California, some crowds defied the nightly curfew and began raiding and vandalizing stores Sunday night.
The entire DC National Guard -- about 1,350 members -- was called out Sunday night to assist police with protests in the city after several fires were set, including in a church just blocks from the White House.
Protesters are sick of the violence, too
"The protesters are people who are well-intentioned and overwhelmingly peaceful," Minnesota Attorney General Keith Ellison said Monday.
But their civil demands for justice have been marred by agitators of different races and ideologies who do not appear to be protesting for Floyd.
Footage of a protest outside Baltimore City Hall late Saturday showed two white men covered in black clothing at the front barricade. One had most of his head and face concealed.
"We were peacefully protesting, and those two guys came to the front and started kicking the barricade and throwing things at the cops," said Denicia B., who posted the video on Twitter.
Denecia said she did not want her last name publicized because "as a black woman, I'm afraid of retaliation. But at this point, the world needs to know what's happening."
"They would then run away, and seconds later the protesters were being tear gassed."
The video, which contains profanity, shows Denicia telling the two white men to stop.
"Don't push the gate! Stop! Stop!" Denicia said. "When you do that, they don't come after you. They come after us!"
Another protester also tells the instigators to stop. "They're going to kill us if you don't chill," he said.
"That's what they already do," one of them replies.
Police chiefs unite with grieving relatives and protesters
Minneapolis Police Chief Medaria Arradondo went to the site of Floyd's death Sunday night, where he spoke to protesters.
What happened to Floyd "was a violation of humanity," Arradondo said. The day after Floyd's death, Arradondo fired four of the officers who were at the scene.
"This was a violation of the oath that the majority of the men and women that put this uniform on, this goes absolutely against it."
Through a video feed Sunday, the chief spoke directly to Floyd's brother, Philonese Floyd. Arrandonado removed his hat and said, "I am absolutely, devastatingly sorry."
Houston Police Chief Art Acevedo also denounced what happened to Floyd. He said he wants his department to provide a police escort when the body is returned to Houston, Floyd's hometown.
And in Flint Township, Michigan, Genesee County Sheriff Chris Swanson put down his baton to listen to protesters. They chanted "walk with us," so he did.
Officials are investigating extremist groups
The FBI and other agencies are tracking groups from both the extreme right and left that are involved in the violence and attacks on police.
Federal law enforcement officials said they're aware of organized groups who are seeking to carry out destruction and violence using the cover of the legitimate protests in Minneapolis and elsewhere.
Those domestic extremist groups include anarchists, anti-government groups often associated with far-right extremists and white supremacy causes, and far-left extremists who identify with anti-fascist ideology.
In the past, some of the groups have been known to organize and travel specifically to confront police and destroy property, federal law enforcement officials said.
Minnesota officials said white supremacists and others were mixing in with legitimate protestors. Authorities there are looking at connections between those arrested and white supremacist organizers who have posted online about coming to Minnesota.
On Sunday, President Donald Trump tweeted that the US will designate Antifa as a terrorist organization -- though experts say that might not be constitutional.
Antifa, short for anti-fascists, describes a broad group of people whose political beliefs lean toward the left -- often the far left -- but do not conform with the Democratic Party platform.
Acting Senate Intelligence Chairman Marco Rubio, a Florida Republican, said outsiders included "a rogues gallery of terrorists from Antifa to 'Boogaloo' groups encouraging and committing violence." Boogaloo is a group often associated with far-right extremist ideology that wants to initiate a civil war.
"Many of these professional agitators don't fit a simple left vs right identity," Rubio said. "They are part of a growing anti-government extremist movement. They hate law enforcement & want to tear the whole system down even if it requires a new civil war."'
Who the looters are
Officials in several cities have said that many looters raiding stores are not there to protest Floyd's death.
Isn some cases, agitators aren't even local. In Miami, Police Chief Jorge Colina said "of the 57 people that were arrested, 13 of those 57 live in the city of Miami."
Some of those who have been arrested are from Michigan, Georgia, New York and at least three are from Minnesota, he said. Others wouldn't say where they're from.
There are other signs that looters aren't really protesters, but rather outside opportunists. In Chicago, Mayor Lori Lightfoot said looters were organized and possibly came from outside of the city.
"There clearly was coordination, they were clearly listening to our radio traffic," she said.
"The number of U-Haul trucks that magically showed up in front of stores, car caravans that dropped people off and broke windows and then were hustling the goods out into the backs of the cars -- absolutely, it was organized."
Correction: An earlier version of this story gave the incorrect number of states where National Guard members are responding to disturbances. It has been updated.