Protesters also threw a flammable liquid inside the Starbucks, whose walls were graffitied with ‘BLM’ and ‘ACAB’, which stands for ‘all cops are b******s’.
The Multnomah County Sheriff’s Office said they stopped the ‘possible arson’ and declared an unlawful assembly, ordering the group to leave.
Protesters had gathered in a park at 9pm and marched together chanting the name of Jason Washington, a black man shot and killed by PSU campus police in 2018.
Police said Kaiave James Douvia, 22, was arrested for criminal mischief, burglary and disorderly conduct, while Connor Austin, 25, was detained for interfering with a peace officer.
They also seized a tire iron, a dumbbell, body armor, gas masks and an umbrella.
Unrest has gripped the Oregon city for more than 100 days following the death of George Floyd, and it has become a symbol of the US’s stark divisions.
It comes as the FBI warned of the potential for more armed clashes in Portland linked to the US election, with the National Guard being readied for riots.
The fiercely polarized vote, which could see President Donald Trump reelected, or defeated by his Democratic rival Joe Biden, has spurred fears of more deadly street violence.
Downtown businesses were boarding up windows once again as protests are planned for either a Trump or a Biden win, or even a state of limbo, with delays in the vote-counting expected nationwide due to a surge in mail-in voting during the pandemic.
‘The thing that is the most concerning to me is the potential for armed clashes between opposing groups,’ FBI Portland Special Agent Renn Cannon told AFP.
‘That could escalate into a dangerous situation where, if tempers are heated, you could end up with an unfortunate or tragic act of violence,’ he added, pointing to a deadly shooting of a far-right supporter in the city in August.
The 250-strong Portland office has devoted additional resources to election crimes including voter suppression as well as fraud and foreign cyber threats, said Cannon.
Meanwhile Governor Kate Brown on Monday issued an executive order handing Portland policing to state forces, effectively overruling the city’s ban on tear gas, and putting the National Guard on standby.
‘This is an election like no other in our lifetime,’ she warned.
Brown’s warnings about white supremacists have drawn scorn from local conservatives including talk-radio host Lars Larson, who Monday accused her of ‘deafening silence’ about ‘Antifa and Black Lives Matter violence’ over five months of protests.
But while Oregon is a safe Democratic state, Portland’s Republican hinterland has made it a focus for protests from all ideologies, with further demonstrators flying in from across the country this summer.
FBI agents are being ‘extra attentive’ to any threats that could ‘reduce the ability for people to exercise their first amendment rights or exercise the right to vote,’ said Cannon.
Officials’ fears of renewed violence were echoed by voters Monday, including restaurant cook Leigh Smith.
‘I’ve seen everybody’s boarding up already and I’m like ‘oh geez,” said the 35-year-old, after mailing her ballot near the downtown courthouse that became an epicenter of earlier demonstrations.
‘It’s really a wild card situation. It could be really chill… it could become chaotic.’
One cause for optimism is that Oregon votes entirely by mail, making lengthy voting lines that could be targeted unlikely on Tuesday, said Cannon.
Of greater concern are multiple protests planned in Oregon for the aftermath of a vote which may not yield a result for days or even weeks, he added.
‘Whether or not those will have an armed component or not, I don’t know,’ said Cannon, with no specific threats currently identified.
One group organizing a rally, the left-wing Democratic Socialists of America’s Portland branch, told AFP it was ‘prepared for right-wing street violence to express frustration about their candidate not winning’ if Joe Biden triumphs.
‘It’s our duty to show up and counter them,’ said co-chair Olivia Katbi Smith, adding that if protesters fail to mobilize in numbers, militias ‘will actually drive around and assault people.’
DSA Portland does not advocate for armed response to right-wing extremists, she added.
If Trump tries to claim an illegitimate victory, Katbi Smith hopes liberal groups will bring out protest numbers approaching the tens of thousands who attended Portland’s 2017 women’s rights march.
‘We’re going to go forward with specific demands about democracy,’ said Katbi Smith, including Trump’s removal or a new vote.
She added: ‘There will be right-wing mobilizations against us after the election.’
America boards up ahead of election storm
Tuesday’s presidential election has the nation on edge and business and property owners in some of America’s major cities are taking no chances in case violence spills out into the streets.
Workers were seen this weekend all across the country boarding up store fronts, business offices, restaurants, banks, hair salons, and other places of commerce as law enforcement warned of possible unrest on Tuesday night.
Business owners are eager to avoid a repeat of the turmoil that followed the May 25 police-involved death of George Floyd in Minneapolis – an event that triggered nationwide rioting and looting.
Retailers have been on edge after raiders earlier this year smashed windows, stole merchandise and, at times, set stores ablaze in Chicago, New York, Los Angeles, Portland and other US cities.
In New York City, the Guardian Angels, a volunteer nonprofit that patrols communities to prevent crime, plans to be out in the streets on Election Night to protect neighborhoods and look out for rioting and looting.
‘We anticipate like a lot of New Yorkers that one side or the other may not be happy with the outcome of November 3rd … but more importantly there are looters and thugs with no political identity who may take advantage of the situation and riot and loot again,’ Guardian Angels founder Curtis Sliwa told WABC-TV.
In New York City, boards went up over many Fifth Avenue storefronts over the weekend.