Police officers help remove the the body of a man who was shot dead amid weekend clashes in Portland, Ore.
FILE - Police officers help remove the body of a man who was shot dead amid weekend street clashes between supporters of President Donald Trump and counterdemonstrators in Portland, Oregon, Aug. 29, 2020.

WASHINGTON - For the first time, a self-identified member of the militant movement known as antifa has been implicated in a fatal shooting and is reportedly under investigation in the killing of a supporter of President Donald Trump on Saturday in Portland, Oregon.  

The left-wing protest movement has resorted to violent measures in the past in opposition to right-wing extremist groups but has stopped short of lethal tactics. 

A small memorial to Portland, Oregon, fatal shooting victim Aaron J. Danielson, 39, of Portland is shown on Monday, Aug. 31, 2020, at the site where he was killed on Saturday, Aug. 29, 2020.

The victim, Aaron "Jay" Danielson, was shot in the chest during violent skirmishes between members of a right-wing group called Patriot Prayer and counterdemonstrators that included antifa and others.  

Police are investigating but have not named a suspect. Portland's largest newspaper, The Oregonian, however, reported that Michael Forest Reinoehl, 48, has been identified by his estranged sister as the gunman.  

"We reached out to police and confirmed that we recognized Michael in the screenshots,” the sister told the paper.  

Asked for confirmation of the reported investigation, a Portland Police Bureau spokesperson said via email, "This is a homicide investigation, and the detectives are actively pursuing the case." 

The FBI said it is supporting the investigation.  

Unusual case of lethal violence 

If Reinoehl is implicated in the case, it would mark the first time in recent years that an antifa supporter has been charged with homicide, said Brian Levin, director of the Center for the Study of Hate and Extremism at California State University.  

"Unlike the white supremacist and the far right, which glorifies mass violence by loners and small cells against minorities and enemies, hard-left violence has generally been less fatal and more directed towards property, racists and to a lesser extent police and journalists," Levin said.  

Gary LaFree, chairman of the University of Maryland's criminology department, said the case could potentially be included in the university's Global Terrorism Database as the first act of terror linked to antifa.

FILE - Antifa counterprotesters, rallying against right-wing group Patriot Prayer, light a smoke grenade in Portland, Oregon, Sept. 10, 2017.

The case comes as President Trump continues to accuse antifa and other radical leftist groups of instigating the violence in Portland and elsewhere, touting his tough-on-crime policies and telling voters that they won't be safe in Democratic candidate Joe Biden's America.  

In a statement released Monday, Biden condemned the violence in Portland. 

“The deadly violence we saw overnight in Portland is unacceptable," Biden said. "Shooting in the streets of a great American city is unacceptable. I condemn this violence unequivocally."

Trump, however, took Biden to task for failing to condemn antifa by name. 

"I don't believe he mentioned the word antifa. Antifa is a criminal organization," Trump told reporters at the White House.   

Opposition to white supremacy 

With roots going back to the rise of fascism in Europe, antifa, short for anti-fascists, is a movement of militants known for their violent opposition to white supremacy. Their tactics range from scouring neo-Nazi message boards to expose their adherents to taking to the streets to disrupt right-wing rallies.

FILE - U.S. Secret Service uniformed officers tear apart barricades as they clash with anarchists and antifa counterprotesters trying to block white nationalists from departing their rally across from the White House, marking the one-year anniversary of the 2017 Charlottesville, Virginia, protests, Aug. 12, 2018.

The movement rose to prominence in 2017 when its supporters, wearing masks and black attire, clashed with far-right groups gathered in Charlottesville, Virginia, to protest the removal of a Confederate general's statute.  

Before Saturday, no antifa member was known to have carried out a killing in the name of the movement.

"What is significant about the Portland killing, though is that earlier the hard left generally adhered to a more toned-down template for conflict that focused on confronting and exposing bigots, seizing turf and low-level criminality," Levin said.

Months of protest 

Portland has been the scene of violent protests since the death in police custody of African American George Floyd on May 25, leading the federal government to send in armed agents to protect an embattled courthouse building.  

Things came to a head in Portland on Saturday when a caravan of Patriot Prayer members and Trump supporters drove through Portland, sparking clashes with Black Lives Matter protesters on the streets.

FILE - Joey Gibson, leader of the right wing Patriot Prayer group, arrives at the scene of a shooting amid weekend street clashes between supporters of President Donald Trump and counterdemonstrators in Portland, Oregon, Aug. 29, 2020.

The Southern Poverty Law Center describes Patriot Prayer as a far-right group that for years has held rallies in progressive cities such as Portland "where they frequently engage in violence against their political opponents."  

Photographs of the shooting aftermath show Danielson wearing a hat emblazoned with Patriot Prayer's insignia.  

It is not clear what led to the shooting Saturday night. Based on video images of the shooting and other evidence, The Oregonian reported that "the victim may have used some type of mace or pepper spray and then collapsed after gunshots ring out."  

WATCH: Who Are Antifa?

Support for antifa, Black Lives Matter 

On social media, Reinoehl, the suspect, documented his staunch support for Black Lives Matter and antifa.

"I am 100% ANTIFA all the way!" the self-described professional snowboarder and contractor wrote on Instagram in June. "I am willing to fight for my brothers and sisters! Even if some of them are too ignorant to realize what Antifa truly stands for."

In another post, he claimed to have served in the army but said he hated it.

"I did not feel like fighting for them would ever be a good cause," he wrote. "Today's protesters and antifa are my brothers in arms. This is a Cause to fight for This truly is fighting for my country!"

On July 3, Reinoehl posted a picture of himself on Instagram lifting a shirt to reveal the words, "Tonight's battle scar thanks to a nasty bean bag shot at me from 20 feet away." 

Two days later, Reinoehl, who was wanted by police on multiple charges in a June 8 speed-racing case, was cited at a Portland demonstration for possessing a loaded gun in a public space, resisting arrest and interfering with police, according to The Oregonian.  

Case of significance 

LaFree, the University of Maryland criminologist, said the case has huge significance for civil society and democracy.  

"We're getting these situations where people with opposing perspectives are going in as volunteers” to enforce their views in violent ways, while the police “are not exactly sure what to do in this circumstance," he said.

"I think it's going to be inevitable if you keep having situations like this, things are going to get out of hand," LaFree said. "I think it's quite a dangerous situation actually."