An Inauguration Day standoff in D.C. between police and anarchist protesters resulted in dozens of arrests, at least one person removed by ambulance and police officers pepper-spraying people to disperse the crowd.

The protesters smashed windows at a bus stop and businesses in the downtown area before congregating in mass in front of the American Health Care Association building on L Street Northwest. Police surrounded a group of about 100 protesters and began arresting them one by one.

At one point Friday afternoon, someone smashed the window of a police vehicle, which quickly sped away.

D.C. police said they have arrested more than 90 people at the protest.

For hours, more and more people gathered outside the line of police blocking the area, chanting and yelling at police. The protest ended in chaos as pink smoke filled the air and police began spraying protesters with pepper spray. Loud bangs were heard in the area.

Protests spread throughout downtown Washington on Friday afternoon, one day ahead of a march expected to bring hundreds of thousands of people to the area. Police were attempting to keep the protests away from the inaugural parade route down Pennsylvania Avenue just blocks away from the White House.

People traveled from around the country to make their voices heard, not all of them anti-government anarchists. Some said they would have been fighting no matter what, but others said Trump's election was a unique motivating factor.

"He's repugnant," said Cody Eckert of California. "If it were any other Republican, I would have stayed home today but he's repugnant and it's imperative for us to be out here today."

"We're putting him on notice," said Debbie Magill, also from California.

Earlier Friday, some of President Trump supporters that did not hold tickets to the inauguration were left furious as they were greeted by protesters that blocked entrances to the National Mall. Protesters, these supporters said, blocked several security checkpoints, telling them: "This entrance is closed."

"What's upsetting me is they want to make sure Trump doesn't have all his supporters in there," Trump supporter Sandy Duncan of Maryland said. "They are making it look like we're not here, we're here."

While many of the protesters said they were out there peacefully and had done nothing wrong, windows were broken in businesses and bus stops in the area and video from the scene showed trash being thrown at police.

Later, a march blocked off 16th Street near the White House and continued onto Interstate 395 with protesters blocking off the freeway for vehicles.

Concussions grenades and tear gas were fired to disperse the crowd, which was growing more violent as the afternoon wore on. Philip Wegmann, a columnist for the Washington Examiner, reported having his phone ripped from his hands and smashed on the ground when he tried to take a photo.

Alexander Martin, from Virginia, was among the peaceful gathering that wanted to send President Trump a message.

"Trump's a loose cannon and he has a really big cannon," Martin said. "We're just here to show that on day one there's dissent."

"Personally, I was trying to contribute my body to a cause," said a man who called himself Charles, who declined to give his real name. "When you're out here with a bunch of people you individually don't get to speak about what your particular cause is, but it's effective for communicating en masse opposition to Trump."

Steve, who also declined to give his real name, said he was trying to show "civil disobedience, voicing strong opposition to Trump's agenda and his Cabinet."

Sean Langille contributed.