Rosenblum announced in a Twitter post that the lawsuit would be filed specifically in response to federal officers allegedly seizing and detaining residents without probable cause and excessive force. The agencies named included U.S. Department of Homeland Security, U.S. Marshals Service, U.S. Marshals Service, U.S. Customs and Border Protection and the Federal Protection Service.
Nightly protests against police violence have attracted hundreds to sometimes thousands in Portland for more than six weeks in the aftermath of the police killing of George Floyd in Minneapolis on Memorial Day.
Since at least Tuesday, federal officers have been using unmarked vehicles to grab protesters off the streets and detain them with little explanation of why they are being arrested in an apparent escalation of federal force, witnesses told Oregon Public Broadcasting.
"I share the concerns of our state and local leaders -- and our Oregon U.S. senators and certain congressional representatives -- that the current escalation of fear and violence in downtown Portland is being driven by federal law enforcement tactics that are entirely unnecessary and out of character with the Oregon way," Rosenblum said in a statement.
"These tactics must stop. They not only make it impossible for people to assert their First Amendment rights to protest peacefully. They also create a more volatile situation on our streets."
The American Civil Liberties Union Foundation of Oregon also filed a lawsuit Friday against the DHS and the U.S. Marshals Service over the federal agencies' treatment of protesters, journalists and legal observers.
Last week police shot a Portland protester in the head with an impact munition, causing serious injuries, OregonLive reported.
Rosenblum announced a state criminal investigation with the Multnomah County District Attorney into the injury. She blamed the incident on a federal police officer.
"The federal administration has chosen Portland to use their scare tactics to stop our residents from protesting police brutality and from supporting the Black Lives Matter movement. Every American should be repulsed when they see this happening. If this can happen in Portland, it can happen anywhere," Rosenblum said.
"With as much lawbreaking is going on, we're seeking to prosecute as many people as are breaking the law as it relates to federal jurisdiction. That's not always happening with respect to local jurisdiction and local offenses. But, you know, this is a posture we intend to continue not just in Portland but in any of the facilities that we're responsible for around the country," he said.
On Saturday afternoon Sen. Jeff Merkley (D-Ore.) announced on Twitter that he and Sen. Ron Wyden (D-Ore.) plan to introduce an amendment to the defense bill to "stop the Trump administration from sending its paramilitary squads onto America's streets."
"We won't let these authoritarian tactics stand," Merkley wrote.
Also Saturday, the New York Times reported on an internal DHS memo that hinted at future encounters in other cities and warned that the federal agent dispatched in Portland were not specifically trained in riot control or mass demonstrations.
"Moving forward, if this type of response is going to be the norm, specialized training and standardized equipment should be deployed to responding agencies."
Tensions between the city of Portland and federal agencies heated up after Acting Secretary Chad Wolf of the Department of Homeland Security arrived downtown on Thursday afternoon, KOIN reported. Federal officers deployed tear gas outside the federal courthouse after protesters stood their ground late Thursday night when they were told to disperse. By the end of the night, 20 people were arrested.
CBP said it arrested "violent anarchists" over the past several weeks, accusing them of damaging and destroying federal property.
CBP Commissioner Mark Morgan tweeted Friday that his agency "will continue to arrest the violent criminals that are destroying federal property and injuring our agents/officers in Portland."
"CBP will restore and maintain law and order."
Two separate marches were scheduled that night, one a "fight for Black Lives," by the PNW Youth Liberation Front against "the rise of fascism and hate in America," according to Radical Guide website. The other a "March for Black Education," which according to the PDX Black Lives Matter Events page was to bring awareness to the lack of black representation in Portland Public Schools and the treatment of Black, Indigenous, and people of color students and faculty.
Early Saturday morning, after Portland police declared the downtown demonstration to be unlawful, federal and local officers advanced on protesters and used tear gas -- whose use has been temporarily restricted in the city -- as well impact munitions and stun grenades at least twice to break up the demonstrations. Multiple outlets with reporters at the scene said it was not clear what precipitated the use of force.
On Saturday afternoon the Portland Police Bureau issued a press release announcing seven arrests and saying PPB did not use tear gas, also known as CS gas, on protesters.
"Beginning tonight command from the Federal Protective Service will not work in the Portland Police incident command center," the release added.
It is not clear when the Federal Protective Service started using the command center, though that aspect of collaboration between the agencies was first mentioned in a July 9 OPB story.
The total number of arrests since federal officers came to Portland has not been disclosed.
Last week federal officers arrested a protester for vandalizing a federal courthouse. According to a series of Portland police tweets, federal officers also arrested two other people for unlawfully pointing lasers into federal officers' eyes and another person for breaking a hole in the door of the federal courthouse with a hammer and striking one of the federal officers who responded to the scene in the head and shoulder with a hammer.