The event has also drawn counterprotestors. CNN reports that about 1,000 law enforcement officers and emergency workers are on hand. The National Guard was placed on standby.

Just as it was set to begin at noon, the city of Charlottesville declared the assembly unlawful, and protestors have been arrested. Video taken just before the march’s scheduled start shows clashes between factions, with some protestors armed with clubs and shields. Injuries are already being reported, and Virginia Governor Terry McAulliffe has declared a state of emergency in response.

Violence had already erupted before the official start of the rally, including last night during a torchlit march on the University of Virginia campus, where police intervention was reportedly minimal.

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Last night’s march was made up predominantly of men in their 20s and 30s, according to reports, who chanted slogans including “White lives matter!” and “Jews will not replace us!”

The Unite the Right rally was nominally planned as a protest against the removal of a statue of Confederate general Robert E. Lee from a city park. But it represents a rising wave of overtly racist political action in the U.S., with scheduled speeches from alt-right leaders including National Policy Institute head Richard Spencer.

Charlottesville was the site of a similar rally in May, which mayor Mike Signer described as “horrific.” There has been no apparent comment on today’s rally from the White House.

President Trump's silence as #Charlottesville roils with racist and fascist provocatation is shameful, irresponsible…and, DEFINING.

— Sen. Patrick Leahy (@SenatorLeahy) August 12, 2017

Donald Trump’s rhetoric has sometimes drawn on white nationalist tropes, and his electoral victory has been celebrated by alt-right groups.