CHARLOTTESVILLE, Va. — The city of Charlottesville was engulfed by violence on Saturday as white nationalists and counterprotesters clashed in one of the bloodiest fights to date over the removal of Confederate monuments across the South.
White nationalists had long planned a demonstration over the city’s decision to remove a statue of Robert E. Lee. But the rally quickly exploded into racial taunting, shoving and outright brawling, prompting the governor to declare a state of emergency and the National Guard to join the police in clearing the area.
Those skirmishes mostly resulted in cuts and bruises. But after the rally at a city park was dispersed, a car bearing Ohio license plates plowed into a crowd near the city’s downtown mall, killing a 32-year-old woman. Some 34 others were injured, at least 19 in the car crash, according to a spokeswoman for the University of Virginia Medical Center.
Col. Martin Kumer, the superintendent of the Albemarle-Charlottesville Regional Jail, confirmed Saturday evening that an Ohio man, James Alex Fields Jr., 20, of Maumee, had been arrested and charged with second-degree murder, three counts of malicious wounding and failing to stop at the scene of a crash that resulted in a death. But the authorities declined to say publicly that Mr. Fields was the driver of the car that plowed into the crowd.
Witnesses to the crash said a gray sports car accelerated into a crowd of counterdemonstrators — who were marching jubilantly near the mall after the white nationalists had left — and hurled at least two people in the air.
“It was probably the scariest thing I’ve ever seen in my life,” said Robert Armengol, who was at the scene reporting for a podcast he hosts with students at the University of Virginia. “After that it was pandemonium. The car hit reverse and sped and everybody who was up the street in my direction started running.”
The planned rally was promoted as “Unite the Right” and both its organizers and critics said they expected it to be one of the largest gatherings of white nationalists in recent times, attracting groups like the Ku Klux Klan and neo-Nazis and movement leaders like David Duke and Richard Spencer.
Many of these groups have felt emboldened since the election of Donald J. Trump as president. Mr. Duke, a former imperial wizard of the Ku Klux Klan, told reporters on Saturday that the protesters were “going to fulfill the promises of Donald Trump” to “take our country back.”
Saturday afternoon, President Trump, speaking at the start of a veterans’ event at his golf club in Bedminster, N.J., addressed what he described as “the terrible events unfolding in Charlottesville, Virginia.”
In his comments, President Trump condemned the bloody protests, but he did not specifically criticize the white nationalist rally and its neo-Nazi slogans, blaming “hatred, bigotry and violence on many sides.”
“It’s been going on for a long time in our country, it’s not Donald Trump, it’s not Barack Obama,” said Mr. Trump, adding that he had been in contact with Virginia officials. After calling for the “swift restoration of law and order,” he offered a plea for unity among Americans of “all races, creeds and colors.”
The president came under criticism from some who said he had not responded strongly enough against racism and that he failed to condemn the white nationalist groups by name who were behind the rally.
Among those displeased with Mr. Trump was the mayor of Charlottesville, Mike Signer. “I do hope that he looks himself in the mirror and thinks very deeply about who he consorted with during his campaign,” he said.
Late on Saturday night, the Department of Justice announced that it was opening a civil rights investigation into “the circumstances of the deadly vehicular incident,” to be conducted by the F.B.I., the United States attorney for the Western District of Virginia, and the department’s Civil Rights Division.
“The violence and deaths in Charlottesville strike at the heart of American law and justice,” Attorney General Jeff Sessions said in a statement. “When such actions arise from racial bigotry and hatred, they betray our core values and cannot be tolerated.”
The turmoil in Charlottesville began with a march Friday night by white nationalists on the campus of the University of Virginia and escalated Saturday morning as demonstrators from both sides gathered in and around the park. Waving Confederate flags, chanting Nazi-era slogans, wearing helmets and carrying shields, the white nationalists converged on the Lee statue inside the park and began chanting phrases like “You will not replace us” and “Jews will not replace us.”
Hundreds of counterprotesters — religious leaders, Black Lives Matter activists and anti-fascist groups known as “antifa” — quickly surrounded the park, singing spirituals, chanting and carrying their own signs.
The morning started peacefully, with the white nationalists gathering in McIntire Park, outside downtown, and the counterdemonstrators — including Cornel R. West, the Harvard University professor and political activist — gathering at the First Baptist Church, a historically African-American church here. Professor West, who addressed the group at a sunrise prayer service, said he had come “bearing witness to love and justice in the face of white supremacy.”
At McIntire Park, the white nationalists waved Confederate flags and other banners. One of the participants, who gave his name only as Ted because he said he might want to run for political office some day, said he was from Missouri, and added, “I’m tired of seeing white people pushed around.”
But by 11 a.m., after both sides had made their way to Emancipation Park, the scene had exploded into taunting, shoving and outright brawling. Three people were arrested in connection with the skirmishes.
Barricades encircling the park and separating the two sides began to come down, and the police temporarily retreated. People were seen clubbing one another in the streets, and pepper spray filled the air. One of the white nationalists left the park bleeding, his head wrapped in gauze.
Declaring the gathering an unlawful assembly, the police had cleared the area before noon, and the Virginia National Guard arrived as officers began arresting some who remained. But fears lingered that the altercation would start again nearby, as demonstrators dispersed in smaller groups.
Within an hour, politicians, including Gov. Terry McAuliffe, a Democrat, and the House speaker, Paul D. Ryan of Wisconsin, a Republican, had condemned the violence.
The first public response from the White House came from the first lady, Melania Trump, who wrote on Twitter: “Our country encourages freedom of speech, but let’s communicate w/o hate in our hearts. No good comes from violence.”
Former President Barack Obama responded to the violence on Twitter with a quote from Nelson Mandela: “No one is born hating another person because of the color of his skin or his background or his religion... People must learn to hate, and if they can learn to hate, they can be taught to love..”
After the rally was dispersed, its organizer, Jason Kessler, who calls himself a “white advocate,” complained in an interview that his group had been “forced into a very chaotic situation.” He added, “The police were supposed to be there protecting us and they stood down.”
Both Mr. Kessler and Richard Spencer, a prominent white nationalist who was to speak on Saturday, are graduates of the University of Virginia. In an online video, titled “a message to Charlottesville,’’ Mr. Spencer vowed to return to the college town.
“You think that we’re going to back down to this kind of behavior to you and your little provincial town? No,’’ he said. “We are going to make Charlottesville the center of the universe.”
Later in the day, a Virginia State Police helicopter crashed near a golf course and burst into flames. The pilot, Lt. H. Jay Cullen, 48, of Midlothian, Va., and Berke M. M. Bates, 40, a trooper-pilot of Quinton, Va., died at the scene. Their Bell 407 helicopter was assisting with the situation in Charlottesville, the Virginia State Police said.
The violence in Charlottesville was the latest development in a series of tense dramas unfolding across the United States over plans to remove statues and other historical markers of the Confederacy. The battles have been intensified by the election of Mr. Trump, who enjoys fervent support from white nationalists.
In New Orleans, tempers flared this spring when four Confederate-era monuments were taken down. Hundreds of far-right and liberal protesters squared off, with occasional bouts of violence, under another statue of Robert E. Lee. There were fisticuffs and a lot of shouting, but nothing like the violence seen in Charlottesville.
In St. Louis, workers removed a confederate monument from Forest Park in June, ending a drawn-out battle over its fate. In Frederick, Md., a bust of Roger B. Taney, the chief justice of the United States who wrote the notorious 1857 Dred Scott decision denying blacks citizenship, was removed in May from its spot near City Hall.
Here in Charlottesville, Saturday’s protest was the culmination of a year and a half of debate over the Lee statue. A movement to withdraw it began when an African-American high school student here started a petition. The City Council voted 3 to 2 in April to sell it, but a judge issued an injunction temporarily stopping the move.
The city had been bracing for a sea of demonstrators, and on Friday night, hundreds of them, carrying lit torches, marched on the picturesque grounds of the University of Virginia, founded in 1819 by Thomas Jefferson.
“We’re going to fulfill the promises of Donald Trump” to “take our country back,” said Mr. Duke, a former imperial wizard of the Ku Klux Klan. Many of the white nationalist protesters carried campaign signs for Mr. Trump.
University officials said one person was arrested and charged Friday night with assault and disorderly conduct, and several others were injured. Among those hurt was a university police officer injured while making the arrest, the school said in a statement.
Teresa A. Sullivan, the president of the university, strongly condemnedthe Friday demonstration in a statement, calling it “disturbing and unacceptable.”
Still, officials allowed the Saturday protest to go on — until the injuries began piling up.
Charlottesville declared a state of emergency around 11 a.m., citing an “imminent threat of civil disturbance, unrest, potential injury to persons, and destruction of public and personal property.”
Governor McAuliffe followed with his own declaration an hour later.
“It is now clear that public safety cannot be safeguarded without additional powers, and that the mostly-out-of-state protesters have come to Virginia to endanger our citizens and property,” he said in a statement. “I am disgusted by the hatred, bigotry and violence these protesters have brought to our state.”
The Republican candidate for governor in Virginia, Ed Gillespie, issued his own statement denouncing the protests as “vile hate” that has “no place in our Commonwealth.”
Mr. Ryan agreed. “The views fueling the spectacle in Charlottesville are repugnant,” he said on Twitter. “Let it only serve to unite Americans against this kind of vile bigotry.”
Correction: August 12, 2017
An earlier version of this article misstated the age of a man arrested after the Charlottesville rally. James Alex Fields Jr. is 20, not 32.