After a year of protests, Portland residents have waning patience for antifa

Rose City Antifa is one of the nation's oldest active antifa groups. Members rarely give interviews, but two who say they are part of antifa agreed to speak to "Nightline" as the situation in their city of Portland, Oregon, has become a prolonged and destructive stalemate.

Rose City Antifa members "Milo" and "Ace" use pseudonyms and they asked that their faces and voices be obscured for this report.

"The use of violence is a tactic of how we keep our communities safe," Milo said.

Much of the blame for the chaos, property damage and violence over the last year have landed on the self-described anti-racist, anti-facist far left organizers. The black-clad coterie entrenched in the city's protest movement now find themselves in a tense showdown with city officials.

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"We've always had protests here. But to see some of the violent acts like the Molotov cocktails and some of the things thrown at officers has been really new to us," Portland's Police Chief Chuck Lovell told "Nightline."

Mayor Ted Wheeler has been outspoken against the group in recent months.

"The self-described anarchists who engage in regular criminal destruction don't want things to open up to recover," he said in a live video conference in April. "The city of Portland will not tolerate criminal destruction for violence ... for those who are involved in it let's make them hurt them a little bit."

"When the mayor says that he wants citizens and his law enforcement officers [to] make protesters 'hurt a little,' that is a pretty explicit threat," Milo said.

Amid the back and forth, Portland residents are left drained from the conflict and are increasingly decrying the property destruction thought to be perpetuated by antifa.

"I feel frustrated that this is all still going on," said Ian Williiams, owner of Deadstock Coffee, a sneaker-themed cafe downtown. "But I also feel frustrated that Black people keep getting killed. I feel frustrated that small businesses really aren't able to be successful during this time, especially in the state of Oregon."

Antifa claims they're defending their city not only against heavy-handed police tactics, but also from threats from far right extremists, groups like the Proud Boys and the Oath Keepers -- leading to fierce standoffs.

"The use of violence is there to maintain safety for us and make sure that when people like Proud Boys or Nazis or fascists come to our city and want to do that harm, then we are not allowing that," Milo said.

They've received a sharp rebuke from the mayor, who is asking residents to help take back their city and be the eyes and ears of the Portland Police bureau.

"These people often arrive at their so-called direct actions in cars. And they're all dressed in all black. Our job is to unmask them, arrest them and prosecute them," Wheeler said at a video conference.

Individuals claiming to be antifa released a chilling video last week, containing a seemingly veiled threat against Mayor Wheeler and publicized his home address.

"The mayor of this city is undeserving of his position. He has made it abundantly clear that windows to him are more important than human lives," an unidentified voice in the video said. "Ted, we are asking for the last time that you resign. Blood is already on your hands, Ted. But next time, it may just be your own."

Neither Milo nor Ace say they know anything about that video to the mayor and defended their role within the community.

"Most of us are in this work to make our communities safe and to make our communities better," Milo said. "When we see that there are people that are coming to our home and to our city advocating violence against people of color, against queer people… then it is our responsibility as community members to confront that. We do not bring that fight. But we will meet it if it comes to us."

The group has become a lightning rod for controversy. They became known at the white supremacist rally in Charlottesville, Virginia, in 2017 when an man punched white nationalist Richard Spencer during an interview.

"Donald Trump wanted to make them a boogeyman for everything," said Mark Bray, a history professor who studies Aantifa. "Certainly prior to Donald Trump being in the White House, antifa was not a household name in the United States."

Despite their notoriety, the group sees their fight as a moral and just one. Milo and Ace say they practice community organizing and empowerment, which includes publicly outing alleged fascists and other dangerous elements.

"A lot of our work is … compiling evidence of people's online personalities and their online conversations and how a lot of times we see far right folks really engaging in hate speech and misogynistic language and threats of violence online," Milo said.

Many here, including some exhausted business owners, seem increasingly receptive to the mayor's tough talk.

"I'm thankful for everybody in Portland who feels the need to fight for justice, fight for rights, fight for safety and everything," Williams told "Nightline." "But it has definitely affected our business, all the protesting and everything, in that people who are coming to visit town actually feel really unsafe."

A year of unrest has at times forced this barista to double as his own security.

"I was standing outside one night and somebody was like, 'Hey, man, I want you to go ahead and get yours, bust the door,'" encouraging him to take part in the destruction, he said. "I was like, 'No, I'm protecting my business.'"

"I guess the message would just be like, well, 'cut it out. Like, why are you even doing this?'" he said. "You really should be pulling up with the nails and hammers and helping me board up, you know, then instead of trying to bust down."

Margaret Carter's legacy of public service runs deep in Portland. She served as the first Black woman in the Portland state senate. She sympathizes with protesters, but is pained by their destructive tactics.

"I marched during the days of trying to make a difference. My voice has always been out there, but never, never did we create violence," Carter said. "When you think in terms of small businesses that are being hit, who are working very hard to just prepare a meal for their families, that really got my heart."

Milo and Ace defend the destruction as a tactic to apply pressure to city leaders.

"There are a lot of reasons why people would engage in property destruction," Milo said. "I think that one of the reasons that people will break windows is a lot of times symbolic of the way that the city will protect things of material value, but not its people."

However, Carter asks whether the protests are truly legitimate or just random acts of looting.

"Some of the people that have been identified was not Black Lives Matter people," she said. "They were young white kids coming from across the country."

Self-styled citizen journalist Garrison Davis has been reporting on Portland's front lines over the past year. He's witnessed sympathies waning for destructive tactics of some protesters.

"There's been a growing animosity towards some of the protests among, you know, the population of Portland," he said. "A lot of the people are tired. A lot of people are exhausted, the police force is getting tired. We're unsure of what direction this will head."