PORTLAND, Ore. (KOIN) — For a third consecutive night, throngs of protesters gathered in downtown Portland in a display of displeasure with the election of Donald Trump to be the nation’s 45th president.

A spontaneous march took place late on Election Night, followed by a more robust protest that marched through Portland on Wednesday. That escalated into graffiti and vandalism that has police on high alert for Thursday’s march.

By 8:30 p.m. Thursday night’s events escalated to the point where Portland Police considered it a riot. Police said it was due to “extensive criminal and dangerous behavior.”

Police warned the crowd that they were subject to arrest for participation in a riot. The crime of riot is a Class C felony. 

Thursday, a crowd gathered at 5 p.m. in Pioneer Courthouse Square, then began to march around 6 p.m. and joined another group gathered at the waterfront.

Hundreds of marchers began blocking traffic, as organizers said they would do. They took over the Hawthorne Bridge, blocking cars and climbing the railings.

There was an altercation on the bridge, which was caught on camera by freelance journalist Crystal Contreras:

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The crowd continued in NE Portland, where protesters spray painted on buildings. The group that came from downtown was set to meet up with another protest group near Lloyd Center at Holladay Park.

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TriMet warned of service delays on Thursday evening as more anti-Trump protests were expected. They closed the MAX platforms at Pioneer Square, Pioneer Courthourse/SW 6th, SW 5/Mill and SW 6/Montgomery at 4:30 p.m. Platforms at the Lloyd Center will close at 7:30 p.m. until further notice, and trains will still travel through the area.

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Mayor Charlie Hales said he supports the peaceful protest of people exercising their Constitutional rights. But, he said, “Walking onto freeways and blocking the MAX light-rail lines is dangerous for everyone involved, and it puts a heavy burden on people just trying to make it home to their families or get to work safely.”

Cleanup crews Thursday morning tried to cover graffiti on the historic Thompson Elk statue in the heart of downtown Portland left by anti-Trump protesters Wednesday night.

Vulgarities were covered by a wrap though some writing can still be vaguely seen on the base of the elk statue, on Main between SW 3rd and 4th. Portland police said they’re preparing for future protests and addressing the vandalism.

“The public should not confuse our lack of taking action last night with an endorsement of criminal behavior. We will adjust accordingly, we may make arrests today or tomorrow for things we saw yesterday.” — PPB Sgt. Pete Simpson

Hales said, “Vandalism and destruction of private and public property in our city cannot, and will not be tolerated. I ask everyone to look out for their fellow Portlanders–we all need to put safety first.”

Portland activist Gregory R. McKelvey, who has been one of the organizers of recent Portland protests connected with Don’t Shoot PDX, said the group is now called Portland’s Resistance. He released the following statement mid-afternoon Thursday:“We are gathering today at Pioneer Square 5 PM. Our group does not condone violence, vandalism or destruction in any way. However, it is not our job to censor anyones activism. If we were to do that, we might as well call the police ourselves. Our job is to lead by example and that example will be peace.”

Wednesday’s protest

Wednesday’s protest began peacefully, but PPB Sgt. Pete Simpson said the tone changed through the night.

“As the night went on, a lot of those folks left, some other folks joined it, and certainly by, you know, 11 o’clock at night it was almost more of a street party,” Simpson said.

Authorities believe members of anarchy groups used the protest as an opportunity to break the law.

“They will show up and hide in the crowd, use it as a way to be anonymous,” Simpson said. “But they are going to be the ones doing graffiti, they are going to be the ones breaking windows.”

He added police are assessing expectations for more protests on Thursday and trying to determine if more unruly actors will be on the streets. 

If police see a heavy presence early on or if they have information, Simpson said, “Our response may be very different than allowing people to just march all over and do things.”

Only one protester was arrested on Wednesday — 27-year-old Christopher Joseph Gourneau, who police said approached a bonfire at the Thompson Elk statue and threw a Molotov cocktail into the fire.

Simpson said there may be more arrests.

“The public should not confuse our lack of taking action last night with an endorsement of criminal behavior,” he said. “We will adjust accordingly, we may make arrests today or tomorrow for things we saw yesterday