Washington DC is bracing for a white nationalist rally organised to coincide with the anniversary of last year's racially charged violence in Charlottesville, Virginia.
The "Unite the Right 2" event was planned for 5.30pm local time on Sunday in Lafayette Square, across the street from the White House.
As the event kicked off, around two dozen white supremacists had arrived to march and hear alt-right leader Jason Kessler speak. In comparison, there were hundreds of counter-demonstrators.
Authorities have promised an enormous police presence to keep both sides apart and avoid the street brawls that broke out last year in downtown Charlottesville.
A local woman, Heather Heyer, was killed when an Ohio man, James Fields, drove his car into a crowd of counter-protesters.
At the time, President Donald Trump said there were "very fine people" on both sides, spurring criticism from across the political divide that he was equating the counter-protesters with the rally attendees, who included neo-Nazis and other white supremacists.
On Saturday, Mr Trump condemned "all types of racism" in a Twitter post marking the anniversary.
Kellyanne Conway, a senior adviser to Mr Trump, said on Sunday that the media was "just not covering" the president's repeated denunciations of white nationalists.
"He's calling for unity among all Americans and he denounced all forms of bigotry and acts of violence and racism," Conway said on ABC's This Week.
Democratic US Representative Elijah Cummings, the top Democrat on the House Oversight Committee, said Mr Trump was not doing enough to disavow racists.
"He has not gone far enough," Mr Cummings said on ABC's This Week.
"I think it's a low bar for the president of the United States to simply say he's against racism. He's got to do better than that. He's got to address the — the people who are spouting racist-type comments and do racial, racist-type acts."
In Washington on Sunday, counter-protesters planned an afternoon program of music, speeches and poetry readings at Freedom Plaza, east of the White House.
Several counter-protesters gathered near the Washington suburban metro station of Vienna, Virginia, where some white nationalists were expected to board trains to take them into the city.
Police used vehicles and traffic cones to seal off the station's parking lot, where about 40 officers in ballistic vests were also deployed.
Paul Wiedefeld, chief executive of the Washington Metropolitan Area Transit Authority, which runs the metro, told reporters at the station that a full blown security operation was in effect to avert the kind of violence that erupted in Charlottesville last year.
"It's all hands on deck," Mr Wiedefeld said.