Scuffles have broke out between police and protesters during an election night demonstration around Washington DC’s renamed Black Lives Matter plaza.
Demonstrators squared off with officers near to the White House, after two men were detained outside the Labourers' International Union building.
It was not clear why they were being held.
Officers on bikes formed a barrier between the men and the crowd as protesters tried to force themselves through.
Chants of "f*** the police" and "no justice, no peace" broke out while demonstrators called on police to release the men.
Some protestors kicked police bicycles while others called for the crowd to not allow them to take away the two detainees. Officers escorted the detained men out through the barrier of bikes.
The incident appeared to be the first instance of significant tension on a night when many predicted major unrest.
Hundreds of people marched through parts of downtown Washington, sometimes blocking traffic and setting off fireworks.
The demonstrations were largely peaceful, with people shouting, "Whose streets? Our streets!" and "If we don't get no justice, they don't get no peace!"
At one point, the marchers stabbed the tires of a parked police van to flatten them.
People gather in Black Lives Matter Plaza near the White House
APHundreds of people also marched in anti-Trump demonstrations in Portland, Oregon, and Seattle, with several arrested.
Pictures from the scene in Washington earlier showed crowds starting to form in the area as night fell on Tuesday night, with demonstrators carrying placards and banners.
Lively anti-Trump demonstrators were seen dancing, singing and chanting as they anxiously waited for the result of the presidential election.
They took up positions by the White House fence, which was plastered with anti-Trump placards.
It came as the first polls closed in Georgia, Indiana, Kentucky, South Carolina, Vermont and Virginia at 12am (uk time).
In DC, there was heavy police presence at the plaza and nearby businesses have been boarded up.
The Washington DC mayor changed the name of the plaza, located outside the White House, to Black Lives Matter Plaza in June.
Mayor Muriel Bowser, a Democrat, also unveiled a two-block long mural painted onto the street leading up to the White House that reads Black Lives Matter.
The mayor approved the plan for volunteers to create the mural in an apparent rebuke of Donald Trump's military response to protests over police brutality against black people.
