Several participants in the "Unite the Right 2" rally, led by organizer Jason Kessler, marched through D.C. from the Foggy Bottom Metro station, outnumbered by chanting counterprotesters downtown.

WASHINGTON — A man was arrested and a group was pepper sprayed by police Sunday in an otherwise peaceful day of protests against what ended up being a small group of white nationalists holding a rally in downtown D.C.

The “Unite the Right 2” rally, led by organizer Jason Kessler, was planned to mark the anniversary of a deadly gathering of white supremacists in Charlottesville, Virginia. Kessler’s group was severely outnumbered by thousands of shouting counterprotesters as they marched through D.C. from the Foggy Bottom Metro station around 3 p.m.

The group headed to Lafayette Square for a rally planned set to begin at 5:30 p.m. and go until 7:30 p.m. They were greeted by boos and calls from counterprotesters: “Nazis go home.”

Shortly after 5 p.m., when rain started to fall in the District, the crowds began to chant their support … for the police horses.

Kessler marches with supporters and police escorts toward Layafatte Square. (Courtesy Wilson Dizard) Courtesy Wilson Dizard The number of police escorts for the white nationalists in D.C. far outnumber the actual white nationalists. (Courtesy Wilson Dizard) Courtesy Wilson Dizard Antifa counterprotesters take to the streets in D.C. during “Unite the Right 2” Sunday. (Courtesy Wilson Dizard) Courtesy Wilson Dizard Anti-Fascists demonstrating on Pennsylvania Avenue during Sunday’s “Unite the Right 2” rally and counterrallies. (Courtesy Wilson Dizard) Courtesy Wilson Dizard A counterprotester holds a sign reading “I ain’t afraid of no ghosts” during the “Unite the Right 2” in Washington, D.C. (Courtesy Wilson Dizard) Courtesy Wilson Dizard A small group of Unite the Right 2 participants, including organizer Jason Kessler, enter the Vienna Metro Sunday afternoon. (WTOP/Max Smith) WTOP/Max Smith One of the many groups at Freedom Plaza for anti-hate rally ahead of a march to Lafayette Square on Sunday, Aug. 12. (WTOP/Keara Dowd) WTOP/Keara Dowd Lots of activity at Freedom Plaza for the DC United Against Hate rally. Those here are planning to march to Lafayette Square at 3. (WTOP/Keara Dowd) WTOP/Keara Dowd Counterprotesters gather at the Vienna Metro station before Unite the Right 2 participants arrive Sunday afternoon. (WTOP/Max Smith) WTOP/Max Smith White nationalist Jason Kessler arrives at the Vienna metro station in Vienna, Va., Sunday, Aug. 12, 2018. White nationalists are gathering in Washington on the first anniversary of their rally in Charlottesville. (AP Photo/Sait Serkan Gurbuz) AP/Sait Serkan Gurbuz Fairfax County Police are lining the entrance over I-66. Metro leaders and workers are going over plans for Sunday’s events. (WTOP/Max Smith) WTOP/Max Smith Metro officials, local police and union representatives were present at Metro’s Vienna station Sunday morning. (WTOP/Max Smith) WTOP/Max Smith At a rally in Booker T. Washington Park in Charlottesville, Virginia, a speaker says, “This is a really big day. They may lock down our city, but they will never lock down our fight.” (WTOP/Max Smith) WTOP/Max Smith ( 1 /13) Share This Gallery: Share on Facebook. Share on Twitter. Share via email. Print.

“I hope the horses get extra treats today,” one counterprotester said.

The horses also received a round of applause as D.C. police asked the groups to disperse around 5:30 p.m., when it became apparent that the white nationalists would not be performing their scheduled rally.

In fact, the white nationalists headed back to Virginia shortly after 5 p.m.

They were taken in vans after a deliberate distraction technique pulled attention to a different area of Lafayette Square. They were then escorted onto the Metro before returning back to Virginia.

D.C. Police Chief Peter Newsham said police arrested John Mulligan, 44, of Pennsylvania after he allegedly pepper sprayed the victim’s face, in a press conference held Sunday evening.

Police immediately arrested and searched Mulligan. They found he was carrying a slingshot, shards of glass, stones and metal bolts.

Newsham also said that police used pepper spray on a group of protesters that had approached officers on motorcycles in the area of 13th and G streets.

“They got very close to officers. One of the officers looked like he was being pushed up against the motorcycle and he deployed his pepper spray,” Newsham said. “We will investigate that incident to see if that use of force was appropriate.”

Plenty of counterprotesters continued to shout their messages as they poured out onto H Street during the evening hours.

Earlier, the white nationalists got on the public transit system from its Vienna station, where they took a private car with a police escort they obtained through a permit. Previously, Metro said there were no plans to provide a “special train” for participants, but would coordinate with other authorities to ensure that Metro riders were kept safe.

Mayor Muriel Bowser dodged a question about whether the group was given special treatment at the Sunday evening press conference. She said she couldn’t talk about Metro operations, but reiterated the how important it was for the safety of all attendees to keep the two groups separate.

Earlier in the conference, she congratulated law enforcement and other groups for keeping order, while allowing all demonstrators to exercise their free speech rights.

“We think we were largely successful in making sure that those First Amendment activities were able to happen and we maintained peace and order in our city,” she said.

During the Metro ride to the protest in the afternoon, Kessler told supporters and media that he thought “white people are a great people” and that they “need a civil rights advocate.”

He insisted he was not Alt-Right.

The roughly two-dozen Unite the Right participants quietly walked through D.C.’s streets with the help of a police escort. Counterprotesters surrounded the white nationalists, carrying signs and chanting, often slinging curses and expletives.

Hundreds of counterprotesters, including DC United Against Hate, New York Black Lives Matter and the Answer Coalition, had gathered in Freedom Plaza, revving up the crowd with chants of “Fight back” and “No KKK, no fascist USA.” They are meeting the white nationalists around Freedom Plaza, McPherson Square, Farragut Square and Lafayette Square.

Sunday morning began with rallies in Charlottesville. A group of people gathered at Booker T. Washington Park around 9 a.m. for anti-racism events such as a singalong, prayer march and other memorials.

It was part of their effort to reclaim the day, which marked one year since a deadly white nationalist “Unite the Right” rally in the city. Heather Heyer, 32, was killed when a car plowed into a crowd of people protesting the white nationalists. Two Virginia State Police troopers died in the helicopter crash as well.

In Charlottesville, it was a somber day, but no major issues were reported. Barriers and checkpoints lined the downtown area. Officers and layers of barricades shielded Confederate statues in the area as well as parts of University of Virginia’s campus.

D.C. Mayor Muriel Bowser elevated the city’s emergency level Thursday. This activated the District’s emergency operations center and made make it easier for D.C. to work with federal and state agencies to respond incidents, according to the mayor’s office.

Mayor Bowser — who had spend the last several days in San Salvador, El Salvador, to begin a sister city relationship — returned to D.C. Sunday to monitor the rallies, WTOP’s news partners at NBC Washington report.

Bowser’s staff told NBC Washington that there was no indication of an increased threat, and that she was returning out of an abundance of caution. She plans to return to El Salvador Monday morning.

D.C. Police and area law enforcement have been preparing a response plan for months; one that is largely based off what did not work in Charlottesville.

“We’re using a number of techniques to keep them separated … We usually don’t like to speak about those because we don’t want to give anyone who might want to come here and create a problem an opportunity to think ahead about tactics wer’e going to be utilizing,” D.C. Police Chief Peter Newsham told WTOP.

WTOP’s Max Smith and Keara Dowd contributed to this report.