A band plays while wearing banana costumes in downtown Portland as people protest white supremacy Saturday.

Three people were arrested following a lengthy demonstration in downtown Portland’s Lownsdale Square park Saturday afternoon, and police are searching for another individual who is believed to have vandalized a war memorial in an adjacent park.

Saturday’s demonstration came in response to a previous social media rumor that the Ku Klux Klan was organizing a white supremacy rally at or around the downtown Portland park Saturday.

No Klan rally took place. It’s not clear if an actual event had been organized.

Shortly after 8 a.m., Portland police tweeted, “The organizer for the (Klan) rally in front of the Multnomah County Courthouse has communicated to PPB he has cancelled the event planned for this morning and does not intend to show up. PPB continues to monitor the situation.”

Counter-protesters showed up regardless, including antifascist activists, or antifa.

According to police, officers attended the event and stayed away while it was peaceful, but officers intervened when “some people in the group began acting in a violent, threatening manner against attendees who were legally capturing photos and videos.”

Heaven Davis, 19, was arrested and charged with criminal mischief.

Brandon Farley, 31, was arrested and charged with disorderly conduct.

Willy Cannon, 25, was arrested and charged with criminal mischief and abuse of a memorial to the dead.

“I want to acknowledge the community members who came down to peacefully assemble and exercise their freedom of speech rights,” Police Chief Jami Resch said in a statement. “Unfortunately, a group of people chose to engage in dangerous, illegal behavior. I appreciate the thoughtful, measured response by our officers and law enforcement partners.”

Resch said the rally meant that other areas of the city were “negatively impacted” because officers were downtown for the event.

Three people were treated for pepper spray exposure, which police said was deployed by “community members.” The police agency said in a statement that officers “did not use force against anyone during this event.”

But officers said demonstrators had weapons. Some used “Metal-tipped umbrellas” to “jab people,” police said, and “chase them down the street.”

Cops said that rocks, concrete, batons, food and cans were thrown at officers and other attendees during the four-hour event.

Police also circulated a photo of a person clad in all black spray-painting the war memorial.

But those attendees were not the bulk of the demonstrators Saturday.

Most of the 200 or so mask-wearing people at downtown Portland’s Lownsdale Square late Saturday morning were there to tap their feet to the live band that was playing. And to eat pizza, boxes of which were delivered shortly after police made an arrest of someone “engaging in criminal activity.”

“Criminals!” screamed a man wearing a bandana over his face.

“Fascists!” yelled another.

“I just came for the dance party,” said a third, quietly, before he laughed uproariously.

Portland police reported that some of the partiers, before they started partying, used pepper spray on others at the park and, when the police arrived, threw “objects” at the officers.

The march was supposed to disband around noon. Shortly before 1 p.m., police tweeted that what appeared to be lit flares were being thrown into the roadway near Lownsdale Square. Shortly after, officials said people were seen “actively defacing” a monument within Chapman Square Park with what appeared to be spray paint, leading to more arrests. By the time the crowds disbanded, at least three people had been arrested.