Noelle Mandolfo, 30, was seen in videos posted on social media being pinned to the ground by federal officers outside the Mark O. Hatfield United States Courthouse in downtown Portland.
Portland protesters have accused the Trump administration of violating their rights.
Noelle Mandolfo was arrested outside the Mark O. Hatfield United States Courthouse in downtown Portland in the early hours of Monday.
Kristen Jessie-Uyanik, 41, said she was with the Wall of Moms outside the Multnomah County Justice Center when she "heard a BOOM and felt something hit my face."
Police were responding to reports of a shot fired in Lownsdale Square Park when someone pointed out a suspicious bag to officers.
Trump can't find federal personnel to do contact tracing for the coronavirus but has found thousands of agents for his secret police to wage war on his own citizens.
"We will not be the people who sat by and watched our neighbors commit these atrocities," one protester said.
The video shows armed law enforcement officers pepper spraying photojournalist and military veteran Mike Hastie during a Portland protest.
Protesters in Richmond, Virginia, clashed with police during a demonstration in support of protesters in Portland, Oregon.
The Portland protests have reached their 60th day.
Protesters face off with federal officers outside the Mark O. Hatfield Federal Courthouse in the center of the city which has seen nearly two months of unrest following the death of George Floyd.
The 18 Portland demonstrators were arrested for alleged criminal conduct, including failing to comply with a lawful order and assaulting a federal officer.
The request was filed after allegations that federal agents had needlessly assaulted protesters and arrested at least one in an unmarked vehicle.
Seattle Mayor Jenny Durkan said the city is "prepared to pursue every legal recourse" if federal agents intervene in this weekend's protests.
In an interview with Tucker Carlson, Steven Miller linked Democrats to the Confederacy and praised federal agents as "heroes", but Portland's mayor wants them gone.
"These parents should be ashamed of themselves," wrote Donald Trump Jr. in a Wednesday retweet of the video.
A federal judge issued an order blocking federal agents from the Department of Homeland Security and U.S. Marshals from targeting legal observers and journalists covering Black Lives Matter protests in Portland, Oregon.
Current and former law enforcement officials told Newsweek that the Trump administration is using elite paramilitary border units in lieu of U.S. troops to confront protests in Portland.
"What is he using them for? For crowd control, for repressing the right of people to protest," the mayor said.
Federal authorities have an internal system that allows them to identify each officer, CBP Acting Commissioner Mark Morgan said.
Christopher David, 53, was seen being beaten with a baton and pepper sprayed in the face by federal agents in a viral video.
Wall of Moms Twitter accounts have popped up for at least 22 other cities and states, suggesting the power of the Oregon-based movement's ability to inspire grass-roots organizing.
A video recorded outside the federal courthouse in Portland, Oregon, shows a protester wielding the lacrosse stick while others use leaf blowers to disperse tear gas.
"The Geneva Convention states that destroying medical equipment is a war crime violation. Yet, here we are in Portland," Dr. Eric Feigl-Ding tweeted.
Ted Wheeler joined protesters outside the Mark O. Hatfield U.S. Courthouse during yet another night of demonstrations in the Oregon city.
Boris Epshteyn has been mocked for using video of unrest under President Donald Trump to show what Joe Biden's America might look like.
Portland City Council voted unanimously in favor of a resolution blocking the local police bureau from working with federal officers in the city.
Some protesters threw flares and other incendiary objects over a fence erected to protect the Mark O. Hatfield U.S. Courthouse.
Jo Ann Hardesty accused Portland police of adopting the same tactics of the civil rights protests. The city's police union chief said her claims were "outlandish."