At least one person has been killed in Virginia after white nationalists clashed with counter-demonstrators and a car plowed into a crowd.
More than 20 people are believed to have been injured in the incident, according to reports. A state of emergency has also been declared in Charlottesville.
A police helicopter, which was monitoring the protests, has crashed, killing the two police officers on board.
The clashes on Saturday morning prompted the governor to declare an emergency and halt a rally over removing a Confederate general's statue from a public park.
"I am heartbroken that a life has been lost here," Charlottesville Mayor Mike Singer said on his Twitter feed.
"I urge all people of good will - go home." He did not give details of who died and what caused the death.
"I am praying that God help us all," Vice Mayor Wes Bellamy said in an interview with CNN. "We are better than this."
A car ploughed into a crowd of nationalists and counter demonstrators in Virginia. Photo: AP
Demonstrators gathered holding torches earlier in the day. Photo Reuters
Tensions in the city intensified when at least one vehicle plowed into a crowd of people gathered in a street two blocks from the park.
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Multiple people were injured in the incident, the Charlottesville Police said.
It was not clear whether this incident was connected to the earlier confrontations. But a video shown on CNN appeared to show a silver sedan driving at high speed into the crowd before reversing.
An injured person is treated after the incident. Photo: AP
One person has died after nationalists clashed with counter-demonstrators and a car ploughed into the crowds. Photo: AP
"We're closely following the terrible events unfolding in Charlottesville, Virginia," US President Donald Trump said at a news conference.
"We condemn in the strongest possible terms this egregious display of hatred, bigotry and violence on many sides."
"We must ALL be united and condemn all that hate stands for," Trump wrote in a Twitter message. "There is no place for this kind of violence in America."
Officials had approved the protest march in downtown Charlottesville but canceled the event and declared a state of emergency after outbreaks of violence.
Charlottesville police said in a statement on Facebook that they and Virginia State Police were at the scene of the incident in the city's downtown.