Updated 9:30 p.m.

Right-wing activists and those protesting their presence converged Saturday on Portland’s downtown waterfront in a much-anticipated confrontation that captivated a nation inflamed by rising division and resentment, with even President Donald Trump entering the fray.

Police mostly succeeded in separating demonstrators on opposite ends of the ideological spectrum as members of the Proud Boys and counterprotesters both arrived at Tom McCall Waterfront Park.

The Proud Boys gathered to condemn self-described anti-fascist activists, or antifa, who publicly confront those they believe espouse racist or bigoted views and who have a large presence in Portland. The groups traded shouts of “USA” and “Go home, Nazis” during the sometimes tense face-off.

After taunts and chants, the showdown devolved into a roving game of cat-and-mouse as packs of political rivals crisscrossed bridges above the Willamette River and police scrambled to keep them apart.

Skirmishes, pepper spray and arrests on the city’s east and west sides followed over the course of hours as crowds of mostly counterprotesters roamed the streets.

Demonstrators dressed in black and masking their faces hurled mayonnaise and smashed windows of at least one shuttle bus carrying right-wing activists.

Police, at one point, declared a civil disturbance.

Yet the powder keg that elected leaders and law enforcement feared could engulf the city largely fizzled. Various factions jockeyed to declare victory.

“We wanted national attention and we got it,” said Joe Biggs, a Florida resident and former InfoWars staffer who organized the right-wing event. “Mission success.”

The Proud Boys describe themselves as “patriots” and “Western chauvinists.” A number of their members are supportive of misogynistic, racist or xenophobic sentiments. Others are prone to violence.

Biggs had called on like-minded people from around the country to decry a recent attack in the city against conservative writer Andy Ngo by black-clad demonstrators, video of which racked up millions of views online and generated days of national headlines.

Participants also backed a U.S. Senate resolution to label antifa as “domestic terrorists” sponsored by Texas Republican Ted Cruz.

Some, including Biggs, had talked openly online about the Portland event and the desire to “exterminate” antifa. Other event supporters posted images on social media depicting graphic beat downs, knives slicing the throats of enemies and corpses in body bags.

Rose City Antifa, Portland’s homegrown, amorphous band of anti-fascist activists, called on supporters to turn out in opposition to the demonstration.

Despite some of the violent rhetoric surrounding the rally, Trump on Saturday morning appeared to amplify those clamoring to crack down on anti-fascists.

"Major consideration is being given to naming ANTIFA an ‘ORGANIZATION OF TERROR,’” the president tweeted. “Portland is being watched very closely. Hopefully the Mayor will be able to properly do his job!”

Portland Mayor Ted Wheeler later fired back at Trump in a CNN interview.

“This is a potentially dangerous and volatile situation,” Wheeler said. “Adding to that noise doesn’t do anything to support or help the efforts that are going on here in Portland.”

At the start of the demonstrations, concrete slabs and a line of police officers formed a barricade beneath the Morrison Bridge to separate the rival groups, with the Proud Boys and their supporters to the south and counterprotesters to the north.

The right-wing activists, some wearing body armor and helmets, burst into chants of “USA,” sang the national anthem and tried to plant an American flag into the ground.

Counterdemonstrators near the Battleship Oregon Memorial Marine Park varied from local Jewish and Buddhist faith leaders, to a marching band sporting bright yellow banana costumes, to protesters wearing all black.

Some members of the rival groups exchanged heated words and goaded one another, though officers kept them mostly at a distance.

Portland police said officers seized multiple weapons from groups, including bear spray, shields and metal poles.

Yet most participants were peaceful.

“We have to show them that we don’t agree with what they stand for,” said Deanna Flores, 62, who came to oppose the Proud Boys. “Portland is for everybody.”

Joey Gibson, a local provocateur leader of the right-wing group Patriot Prayer, later arrived in the morning holding an American flag and wearing a red Make America Great Again baseball cap.

“I’m just here for the ride,” said Gibson, who was booked Friday into the Multnomah County jail on a felony rioting charge stemming from a May 1 fight outside a Northeast Portland cidery. He was released hours later on bail.

After about 90 minutes the showdown dissipated and people went on the move. The Proud Boys and their supporters began to march over the Hawthorne Bridge, which had been closed earlier in the day.

Police escorted the group across the bridge and prevented counterprotesters from following.

"It wasn’t planned. It wasn’t orchestrated,” said Sgt. Brandon White, a spokesman for the Multnomah County Sheriff’s Office. “We had a request that they would like to leave the area and so we facilitated.”

Later, counterdemonstrators crossed over the Steel Bridge in search of their adversaries. By then, many of the Proud Boys and their supporters had taken off. Some later decamped to Bagley Community Park in Vancouver for a gathering and barbecue.

As the afternoon wore on, police made at least 13 arrests around town as people posted video showing multiple confrontations. Demonstrators often wandered into the street, sometimes blocking traffic, chanting and beating drums. Many held cellphones aloft taking it all in.

In one flare-up, a large group of left-wing protesters encircled right-wing activist John Turano — known as “Based Spartan” — and his adult daughter, threatening and chasing them. The pair wore American-flag garb and Turano had on a vest that on the back read: “I hate the left n racism.”

Police, who estimated more than 1,200 demonstrators altogether, said they were clambering to continue to try to keep the opposing groups apart. They also reported six injuries, all minor, including a person officers found hurt and sent to a hospital in what turned out to be an unrelated traffic incident.

More than 700 law enforcement officers from 15 agencies worked on crowd control, police said.

By late afternoon, with the clashes abating, a group of left-wing protesters gathered at Pioneer Courthouse Square and streets near it.

At an early evening press conference, the mayor thanked police for what he described as a mostly nonviolent event.

Wheeler also took aim at Biggs, claiming his efforts are costing the city millions of dollars and that, in a national culture of fear caused by hate crimes and mass shootings, Biggs is feeding that sense of unease.

Portland Police Chief Danielle Outlaw said the bureau achieved its two goals for the day: keeping people safe and allowing the public to exercise its free-speech rights.

Outlaw said officers were involved in six “force events,” one involving pepper balls and the others involving takedowns of people resisting officers.

Those arrested face allegations of disorderly conduct, interfering with police, resisting arrest and weapons, she said.

The Proud Boys, meanwhile, issued a press release saying they plan to return to Portland in a month unless the city does more to crack down on anti-fascists.

Effie Baum, an organizer with Popular Mobilization, or PopMob, which helped plan the counterprotests, said they’d be ready.

“We built a very diverse coalition of people who turned out to say that hate is not welcome here," Baum said. “When the Proud Boys come back, there will be even more of us.”

Oregonian/OregonLive staffers Jim Ryan, Everton Bailey Jr., Eder Campuzano, Jayati Ramakrishnan, Noelle Crombie, Dave Killen, Kale Williams, Mark Graves, Diana Kruzman and Brooke Herbert contributed to this report.

-- Shane Dixon Kavanaugh; 503-294-7632

Email at skavanaugh@oregonian.com

Follow on Twitter @shanedkavanaugh

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