Anti-fascist protesters descend on white nationalist conference in Washington, DC

Anti-fascist demonstrators descended upon the Ronald Reagan Building in downtown Washington, D.C. on Saturday to protest a conference held by the National Policy Institute, a white nationalist think tank headed by supremacist Richard Spencer.

Spencer and other prominent far-right activists, including British-born paleoconservative Peter Brimelow and anti-Semitic retired professor Kevin MacDonald, were joined by hundreds of attendees. Outside, dozens of demonstrators chanted "we don't want a white state, we say no to racist hate" and "go home Nazi scum."

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Police detained at least two people after one of the white supremacist activists emerged and began filming and taunting the protesters, leading to a fight.

Inside, Spencer painted the protesters as the real "fascists" attempting to prevent members of the movement from meeting. He also praised the election of Republican President-elect Donald Trump as the dawning of a new era for the loosely organized, mostly digital collective of far-right and white supremacist activists sometimes referred to as the alt-right.

"The Trump movement was kind of a body without a head," Spencer said. "The alt-right, as an intellectual vanguard, can complete Trump."