An Air Force sergeant accused of killing two law enforcement officers in California last year was part of a rightwing militia known as the Grizzly Scouts that held firearms trainings, scouted protests, and laid out terms of “war” against police, a newspaper reported Monday.

The Santa Cruz Sentinel cited court documents that show the suspected gunman, Steven Carrillo, was not a lone actor but a member of an anti-government group that was preparing for more deadly attacks on law enforcement.

The court filings reveal the most extensive details yet on the investigation into the May 29, 2020 fatal shooting of Federal Protective Service Officer Dave Patrick Underwood in Oakland and the June 6, 2020 killing of Santa Cruz Sheriff Sgt. Damon Gutzwiller in an ambush in the community of Ben Lomond. Carrillo has pleaded not guilty to both killings.

Most members of the Grizzly Scouts are still at large, federal prosecutors said. The group identifies with a loosely-affiliated, nationwide militia movement that uses the name “Boogaloo” and favors Hawaiian shirts and violent rhetoric, but the Scouts’ activities appear to be more carefully plotted, the newspaper reported.

The court filings were submitted in the case against four other alleged Grizzly Scouts members, including the group’s leader, who are accused of destroying evidence relevant to the Underwood and Gutzwiller murder investigations.

They were written as part of a failed attempt to keep all four defendants in jail pending trial. A federal magistrate ultimately decided three of them were not a danger to the community and did not pose flight risks.

In April, a federal grand jury indicted Jessie Alexander Rush, 29, of Turlock; Robert Jesus Blancas, 33, of Castro Valley; Simon Sage Ybarra, 23, of Los Gatos; and Kenny Matthew Miksch, 21, of San Lorenzo, on charges of conspiracy to obstruct justice. Blancas, the only defendant who remains in jail, also faces a child enticement charge related to alleged sexual conversations with a teen girl that were discovered during the investigation.

The Associated Press was unable Monday to locate lawyers who could speak on their behalf.

The filings not only confirm Carrillo as one of the militia’s roughly 25 members, but detail the group’s alleged activities in mid-2020: trainings near Rush’s home in Turlock, the creation of a “Quick Reaction Force” or QRF, and plans to send a member to scout out a protest in Sacramento.

The filings allege that, in a document entitled “Operations Order,” the militia described law enforcement officers as “enemy forces” and spoke of the possibility of taking some prisoner, writing that, “POWs will be searched for intel and gear, interrogated, stripped naked, blindfolded, driven away and released into the wilderness blindfolded with hands bound.”

Rush previously served in the U.S. military, making him the second known member of the militia, along with Carrillo, with military experience.

The group also allegedly discussed ways to stir up violence between Antifa groups and police. Blancas allegedly wrote that he was “totally down” to disguise himself as an Antifa member and spark a violent conflict.

“It’s the tactically sound option,” Blancas told other militia members, according to prosecutors.