Several thousand supporters of US president Donald Trump gathered in Washington to protest against the country’s election results.
There were clashes with counter-protesters on Saturday evening, with at least one stabbing and 20 arrests.
Several other US cities saw gatherings of Trump supporters unwilling to accept Democrat Joe Biden’s Electoral College and popular vote victory.
Cries of “stop the steal” and “count every vote” continued in spite of a lack of evidence of voter fraud or other problems that could reverse the result.
After night fell, the relatively peaceful demonstrations in Washington turned from tense to violent.
Videos posted on social media showed fistfights, projectiles and clubs as Trump supporters clashed with those demanding they take their banners and leave.
The tensions extended into Sunday morning. A variety of charges, including assault and weapons possession, were filed against those arrested, officials said. Two police officers were injured and several firearms were recovered.
Mr Trump himself had given an approving nod to the gathering on Saturday morning by dispatching his motorcade through streets lined with supporters before rolling on to his Virginia golf club.
People chanted “USA, USA” and “four more years,” and many carried American flags and signs to show their displeasure with the vote tally and insistence that, as Mr Trump has baselessly asserted, fraud was the reason.
“I just want to keep up his spirits and let him know we support him,” said one loyalist, Anthony Whittaker of Winchester, Virginia. He was outside the Supreme Court, where a few thousand assembled after a march along Pennsylvania Avenue from Freedom Plaza, near the White House.
A broad coalition of top government and industry officials has declared that the November 3 voting and the following count unfolded smoothly with no more than the usual minor hiccups — “the most secure in American history,” they said, repudiating Mr Trump’s efforts to undermine the integrity of the contest.
In Delray Beach, Florida, several hundred people marched, some carrying signs reading “count every vote” and “we cannot live under a Marxist government”.
In Lansing, Michigan, protesters gathered at the Capitol to hear speakers cast doubt on results that showed Mr Biden winning the state by more than 140,000 votes.
Phoenix police estimated 1,500 people gathered outside the Arizona Capitol to protest against Mr Biden’s narrow victory in the state. Protesters in Salem, Oregon, gathered at the Capitol.