Black-clad activists angry about US President Donald Trump's inauguration smashed store car windows and blocked traffic in Washington on Friday and fought with police in riot gear who responded with tear gas and stun grenades.
About 500 people, some wearing masks, marched through the city's downtown, using hammers to claw up chunks of pavement to smash the windows of a Bank of America branch and a McDonald's outlet, all symbols of the American capitalist system.
The crowd chanted anti-Trump slogans and carried signs with slogans including "Make Racists Afraid Again," a play on the New York businessman-turned-politician's "Make America Great Again" campaign slogan.
The incident occurred about 90 minutes before Mr Trump was sworn in at the Capitol a couple of kilometres away.
Police have detained around 100 people so far, and have charged numerous people with rioting.
The group of detainees became a flash point after Trump was sworn in, when a crowd of several hundred that had formed to call for their release turned violent, with some throwing bottles and rocks at police who responded with tear gas and stun grenades.
Two police officers sustained minor injuries from people who were trying to avoid arrest, police said.
Protests continued after the inauguration, with clashes between heavily-armed police and activists caught on camera. Water cannons, chemical sprays and stun grenades can be seen being used on the demonstrators.
"The message I want to send is that Trump does not represent this country. He represents the corporate interests," said Jessica Reznicek, a 35-year-old Roman Catholic aid worker from Des Moines, Iowa, who was part of the protest but did not participate in the violence.
Not far from the White House, protesters scuffled with police, at one point throwing aluminium chairs at an outdoor cafe.
Bob Hrifko, a member of the "Bikers for Trump" group in town to celebrate the inauguration, was struck in the face when he tried to intervene.
"I know, law and order and all that. We need more order. This ain't right," said Hrifko, who was bleeding from a cut under his eye.
The number of people who turned out to view the midday swearing-in, on a grey day threatened by rain, appeared to be significantly smaller than the estimated 2 million who turned out for now-former President Barack Obama's first inauguration in 2009.
Overhead video of the National Mall showed sections of the white matting laid down to protect the grass were largely empty.
More people were expected to be on hand when Mr Trump and his entourage travel along Pennsylvania Avenue to the White House later Friday afternoon.
Earlier, liberal activists with a group called Disrupt J20 intermittently blocked multiple security checkpoints leading to the largest public viewing area for the inauguration. Several were led away by police.
Disrupt J20 protest organiser Alli McCracken, 28, of Washington, said the group was voicing its displeasure over Trump's controversial comments about women, illegal immigrants and Muslims.
Tensions were high on the streets of Washington, with scuffles breaking out between Trump supporters and opponents.
People reacted across the world.
In Tokyo, several hundred people, most of them expatriate Americans, protested against Mr Trump. In London, activists draped a banner across the British capital's iconic Tower Bridge reading "Build bridges not walls," a reference to Trump's promise to wall off the US-Mexico border.
But in Moscow, Russians hoping Trump will usher in a new era of detente with their country celebrated his inauguration. Russian nationalists held an all-night party at what used to be the main Soviet-era post office in Moscow.
The US Secret Service, Washington police and other law enforcement agencies had about 28,000 officers in place to secure downtown Washington.
Reuters / Newshub.