CHARLOTTESVILLE, Virginia (CNN) -- One person died when a car plowed into a crowd following a dispersed gathering of white nationalists and counterprotesters in Charlottesville.
Shortly before the attack Saturday, fistfights and screaming matches erupted between counterprotesters and white nationalists protesting the removal of a confederate monument. The clashes led to the cancellation of scheduled protests, sending demonstrators from both sides marching on nearby streets. A few hours later, a car slammed into a throng of counterprotesters.
Here's what we know:
Counterprotesters met white nationalists and other right-wing groups at the site of Saturday's "Unite the Right" event hours before the rally was set to start.
Clashes broke out and police began to disperse crowds.
Local officials declared the rally an "unlawful assembly" and Virginia Gov. Terry McAuliffe declared a state of emergency.
About two hours later, a gray Dodge Challenger rammed into a crowd of counterprotesters walking down a street in downtown Charlottesville.
The driver slammed the car in reverse at high speed and left the site of the crash. He was arrested later that afternoon.
A 32-year-old woman was killed in the car-ramming incident, Charlottesville Police Chief Al Thomas said.
A total of 19 others were also hurt, including five people still in critical condition Sunday, a spokeswoman for the University of Virginia Medical Center said.
Two Virginia State Patrol troopers died when a helicopter crashed in a wooded area near Charlottesville after monitoring Saturday's events. The pilot, Lt. H. Jay Cullen, 48, and Trooper Berke M.M. Bates, who would have turned 41 on Sunday, were killed. Authorities are investigating the cause of the crash.
City officials say at least 15 others were wounded in events associated with the scheduled rally.
The driver, James Alex Fields Jr., 20, of Maumee, Ohio, is being held at a Virginia jail on suspicion of second-degree murder, malicious wounding and failure to stop in an accident that resulted in death, said Superintendent Martin Kumer with the Albermarle-Charlottesville County Regional Jail.
Fields' mother, Samantha Bloom, told CNN affiliate Toledo Blade, her son told her last week he was going to an "alt-right" rally, but she was not involved in his political views. CNN's attempts to reach Bloom were unsuccessful.
The Department of Justice and the Federal Bureau of Investigations have launched a civil rights investigation into the deadly crash.
Three other men were arrested Saturday. One of them faces a charge of carrying a concealed handgun and the other is charged disorderly conduct. The third man, originally from Virginia, was arrested on suspicion of assault and battery.
Federal authorities launched a civil rights investigation hours after the incident.
Attorney General Jeff Sessions said US Attorney Rick Mountcastle is leading the investigation.
"The violence and deaths in Charlottesville strike at the heart of American law and justice. When such actions arise from racial bigotry and hatred, they betray our core values and cannot be tolerated," Sessions said in a statement. "Justice will prevail."