On Jan. 2, 2016, in a remote stretch of southeastern Oregon, a cadre of anti-government militiamen carrying pistols and long guns stationed themselves at the headquarters of the Malheur National Wildlife Refuge, a federally owned park. Their armed occupation ended 41 days later with one protester shot dead by police and more than two dozen others facing federal charges.

Now, investigators commissioned by the Washington State House of Representatives say the anti-government occupiers had a high-profile accomplice: a Republican state legislator known for his extremist views.

An official report released late Thursday found that Washington state Rep. Matt Shea (R) had “participated in an act of domestic terrorism.”

Shea, whose ties to the Patriot movement and anti-government militias were explored “Bundyville: The Remnant,” once introduced legislation to cut Washington state in half to establish a “Liberty State” in deep-red eastern Washington where citizens would have unfettered access to guns, and church and state would walk hand-in-hand. The new report found that he had close relationships with members of armed militias and used them to intimidate opponents.

Soon after the Washington state House of Representatives received the report on Thursday, the state’s House Republican Caucus erased Shea from its website and severed ties with the six-term legislator who represents Spokane Valley, a suburb that stretches from Spokane’s edges to the Idaho border. Shea was stripped of his committee assignments and denounced by caucus leadership.

“He should resign,” Washington State House Minority Leader J.T. Wilcox (R) wrote on Twitter. “He cannot use House Republican staff, he cannot meet with the caucus, his office will be moved.”

Spokane Sheriff Ozzie Knezovich, who has feuded with Shea for years, told a local reporter: “I believe there’s enough to charge Shea with domestic terrorism, if not treason.”

Shea refused to speak to the authors of the report. He rarely speaks to reporters and ignored interview requests from local journalists Thursday. The lawmaker did not return calls and emails from The Washington Post. However, he took to Facebook to speak directly to his core supporters, who showered him with prayers and support in the comments.

“Like we are seeing with our President this is a sham investigation meant to silence those of us who stand up against attempts to disarm and destroy our great country,” Shea wrote late Thursday. “I will not back down, I will not give in, I will not resign. Stand strong fellow Patriots.”

Many of the findings laid out in Thursday’s report had been previously documented by journalists covering the Pacific Northwest since Shea first won a seat in the state legislature in 2008. The report includes 17 pages of references, which point to news articles from the Spokesman-Review, Inlander, Oregon Public Broadcasting and the Guardian, among others.

The report, authored by independent investigators with “extensive experience in career law enforcement” from Rampart Group, found that Shea had used “intimidation tactics” against a political opponent, “condoned violence,” and “engaged in counterintelligence gathering and acted in opposition to the lawful efforts of federal, state and local law enforcement.”

In 2012, investigators found, Shea went to the home of a Democrat challenging him in an election and took a photo in front of the house. He posted the photo on Facebook, including the location of the nearest intersection, and refused to delete the post. “Shea engaged in intimidation tactics against a political opponent,” the report said. “The posting was viewed as a direct act of intimidation and threat.”

That same year, he flashed an unlicensed gun at a driver during a road rage incident but avoided criminal charges.

In private chats with far-right extremists, Shea offered to perform background checks on political rivals, advocated for spying on activists, and encouraged violence against his perceived enemies, the Guardian reported in April.

He also authored, “The Biblical Basis of War,” a four-page document that encouraged training adults and children to fight in a holy war, the report said. “If they do not yield,” Shea wrote of an imagined enemy, “kill all males.” Shea publicly admitted to writing the document, which he claimed were sermons on the history of warfare in the Bible.

In late 2015, Shea formed the Coalition of Western States, or COWS, a group of right-wing lawmakers in the West with ties to sovereign citizens and rogue ranchers who refuse to pay grazing fees to feed their cattle on federally owned land. Oregon Public Broadcasting’s John Sepulvado first reported the likely coordination between COWS, led by Shea, and the leaders of the Malheur occupation. But Thursday’s 108-page investigation revealed new details that tie Shea to the early stages of planning and accused him of distributing military-style operation plans to the occupiers.

Multiple witnesses told the independent investigators that Shea joined four phone conversations with anti-government militant Ammon Bundy and other Patriot-movement leaders to plan the occupation at the Malheur refuge to protest the arrest of two Oregon ranchers. Those men had been found guilty of arson after setting fires on public land to obscure the illegal slaughter of deer. While the armed occupiers lived in the national refuge headquarters, Shea, an Army veteran, emailed at least two detailed plans advising the armed militia members how to continue their standoff with federal agents, the report said.

One week into the standoff, Shea and several other legislators from COWS traveled to Burns, Ore., to question the sheriff and pressure him to intervene on behalf of the militia groups. Shea referred to the federal Bureau of Land Management as “terrorists” during the conversation, the report said.

On the last day of the occupation, after police fatally shot one of the right-wing protesters, Shea wrote on his Facebook page: “After much prayer, I am afraid violence might be necessary to take back our country.”

State legislators have sent the investigation’s findings to the FBI, the Seattle Times reported.

Washington Gov. Jay Inslee (D) denounced Shea, calling the report “disturbing” and “unacceptable.”

Others officials are calling for action.

“This is about a state lawmaker who, according to the investigative findings, engaged in an act of domestic terrorism rather than choosing political or legal avenues to change laws and policies he disagrees with,” Democratic House Speaker Laurie Jinkins told the Times. “This is why we believe formal action needs to be taken that sends a clear message upholding the values of a free and democratic society, and supports the safety of all Washingtonians.”