The unrest was fueled by the death in Minneapolis of George Floyd, a handcuffed black man who pleaded for air as a white police officer pressed a knee on his neck.
Curfews were imposed in places around the U.S., including Atlanta, Chicago, Denver, Los Angeles, San Francisco and Seattle. About 5,000 National Guard soldiers and airmen were activated in 15 states and Washington, D.C.
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Here are the latest updates from across the country:
In Minneapolis, the city where the protests began, police, state troopers and National Guard members moved in soon after an 8 p.m. curfew took effect Saturday to break up demonstrations. The show of force came after three days in which police largely avoided engaging protesters, and after the state poured more than 4,000 National Guard troops into Minneapolis. Authorities said that number would soon rise to nearly 11,000.
At the intersection where Floyd was killed, people gathered with brooms and flowers, saying it was important to protect what they called a "sacred space." The intersection was blocked with the traffic cones while a ring of flowers was laid out.
County Commissioner Angela Conley showed up shortly after the curfew lifted, saying that police had trampled flowers and photos of Floyd. "The community needs healing, and what happened last night only exacerbated the pain that's been felt," she said of police action.
New York City officials were looking for a peaceful way forward as the city entered the fourth day of protests against police brutality that have left police cars burned and led to the arrest of hundreds of people.
Mayor Bill de Blasio said Sunday that city police showed "tremendous restraint overall" but that he was concerned about video showing two police cruisers lurching into a crowd of demonstrators on a Brooklyn street.
He was appointing two city officials to conduct an independent review of how the protests unfolded and how they were handled by the police. New York City police said 345 people were arrested, 33 officers were injured and 27 police vehicles were damaged. There were no major injuries reported.
Armed National Guard soldiers patrolled the streets of Los Angeles on Sunday as the city began cleaning up after a night of violence that saw demonstrators clash repeatedly with officers, torch police vehicles and pillage businesses.
Fire crews responded to dozens of blazes, and scores of businesses were damaged. One of the hardest-hit areas was around the Grove, a popular high-end outdoor mall west of downtown where hundreds of protesters swarmed the neighborhood, showering police with rocks and other objects and vandalizing shops. One officer suffered a fractured skull, Los Angeles Police Chief Michel Moore said.
When the curfew took effect at 8 p.m., police moved aggressively to get people off the streets and there was no repeat of the late-night rampage that occurred downtown Friday night and led to more than 500 arrests.
While Chicago officials took extraordinary steps Sunday to patrol and restrict access to the city's downtown in the hopes of preventing further chaos after a night of protests over the death of George Floyd, reports of vandalism and unrest cropped up throughout the day in the city's neighborhoods and suburbs.
Vandals smashed store windows at a shoe store and cellphone shop in the heavily-Mexican Little Village neighborhood. Multiple suburban shopping malls were closed out of caution, including in North Riverside where police reported a "large disturbance."
The unrest spread from downtown Chicago after a weekend of chaos, as peaceful protests devolved into violence and destruction. By Sunday, six people were shot in Chicago, one fatally, and 240 people were arrested in connection with the demonstrations, police said.
Officials in Philadelphia announced plans to close off much of the center of the city Sunday after peaceful protests over George Floyd's death turned into a night of destruction with store windows smashed near City Hall, merchandise taken from stores and police and other vehicles and structures set afire.
By Sunday, at least 13 police officers were injured in Philadelphia, and at least four police vehicles were set on fire. More than 200 people were arrested as fires and looting engulfed Center City.
"It only hurts the cause," said Danielle Outlaw, head of the police force.
She said much of Center City would be blocked off, affecting roads, bridges and expressway entrances and exits as well as the city's transit agency. The Ben Franklin Bridge between Philadelphia and Camden, New Jersey, was closed until further notice.
An 8 p.m. curfew in the city announced earlier was moved up to 6 p.m. Sunday, and retail establishments were ordered to close immediately with people cleaning or securing vandalized properties ordered to finish up and return home by 5 p.m. so the curfew could be enforced.
Texas Gov. Greg Abbott declared a state-wide disaster Sunday following weekend protests that have turned violent and destructive.
In Texas, much of the demonstrating was peaceful, but the protests became violent Saturday with fires being lit, stores broken into and robbed and people hurt.
Police used tear gas to disperse some of the crowds and said they arrested more than 200 people between Dallas, Houston and Austin.
The mayor of Houston says the body of George Floyd will be returning to Texas. Houston Mayor Sylvester Turner didn't offer additional details Saturday.
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San Francisco's mayor and police chief said Sunday the city's 8 p.m. curfew will be extended indefinitely and that people who are out after that time will be stopped.
Mayor London Breed said Gov. Gavin Newsom had approved sending in about 200 extra officers from other agencies.
Breed, who grew up in San Francisco, expressed sadness about the destruction but said she was not going to tolerate the violence. She said the fire department was inundated with calls because of fires and medical emergencies and had firebombs thrown at them.
The mayor of the nation's capital said Sunday that violence and vandalism from the previous night's protests were committed by "an organized group that appeared more bent on destruction than protest."
Muriel Bowser also acknowledged what she described as the legitimate grievances of the peaceful protesters, incensed over the death of Floyd and other black Americans killed in altercations with police officers.
In a news conference Sunday, Police Chief Peter Newsham said 17 protesters were arrested and he expected more arrests as police go over security camera footage.
Three Secret Service vehicles were damaged and one police officer had a broken leg from a thrown rock. A contingent of 500 members of the D.C. National Guard remains on standby and will continue to be deployed to assist local security, Bowser said.
Saturday's protests took place one day after Bowser had ended a three-month-old stay-home order and launched the first phase of the District of Columbia's reopening plan.
Atlanta's mayor extended a curfew another night Sunday and Georgia's governor authorized up to 3,000 National Guard troops to be deployed across the state to respond if needed to protests over the deaths of George Floyd in Minnesota and Ahmaud Arbery in Georgia.
Guard soldiers had helped enforce a 9 p.m. curfew Saturday in Atlanta, where violence has marred otherwise peaceful protests since Friday. Gov. Brian Kemp said more would be ready Sunday for demonstrations planned in Athens, Savannah and other cities.
Atlanta Mayor Keisha Lance Bottoms signed an executive order Sunday extending the curfew in the city, according to text and email notifications sent to residents. It takes effect at 9 p.m. Sunday and will end at sunrise Monday.
Atlanta police said Sunday they had arrested more than 150 people overnight as protesters threw rocks at officers and broke windows in the downtown area. That brought the total number of arrests over two nights of protests to nearly 230.
Detroit Mayor Mike Duggan has instituted a curfew beginning Sunday.
It starts at 8 p.m. and extends to 5 a.m. Duggan told reporters Sunday that the curfew "isn't intended for Detroiters."
City officials are hoping the curfew keeps people who don't live in Detroit from coming into the city instigating violence during the protests. The curfew doesn't apply to people going and coming home from work. City buses will be operating.
This comes after Duggan announced that nearly two-thirds of the 60 people arrested Friday night during protests in downtown Detroit over the death of George Floyd in Minneapolis were from the city's predominantly white suburbs.