Three alleged members of a white supremacist group "The Base" apparently hoped a gun rights rally in Richmond, Virginia, would spark a civil war, according to court records. Federal prosecutors argued that the men, who were arrested last week, should be detained pending trial, indicating they are a part of a "domestic terrorism investigation."

The three men — Brian Lemley, Jr., William Garfield Bilbrough IV and Canadian national Patrik Jordan Mathews — were arrested on federal firearms charges in the days before the rally.

"Derail some f***ing trains, kill some people, and poison some water supplies. You better be f***ing ready to do those things," Mathews allegedly said, according a video he created on December 1 in which he is wearing a gas mask to distort his voice and hide his face. "If you want the white race to survive, you're going to have to do your f***ing part."

Get Breaking News Delivered to Your Inbox

Investigators were able to obtain this information in part through surveillance warrants obtained under Title III, which permitted law enforcement to install a closed-circuit camera and microphone in Lemley and Mathews' home in Delaware.

Authorities also executed a so-called "sneak-and-peek" warrant on that residence, which allows entry to the premises without the knowledge of the residents. During that search, agents found Base propaganda flyers, the parts needed to make an assault rifle, and videos created by Mathews where he "espous[es] violent, anti-Semitic, and racist language" located on his computer.

Patrik Jordan Mathews seen wearing a gas mask in this screengrab from a video created in December. Federal court exhibit

The surveillance devices also caught Mathews and Lemley discussing potential violence during their trip to Virginia.

"Here's the thing to, you want to create f***ing some instability, while the Virginia situation is happening, make other things happen, derail some rail lines, f***ing like shut down the highways, oh road block, great lets [sic] shut down the rest of the roads, you know, you can kick off the economic collapse of the U.S. within a week," Mathews allegedly told Lemley on December 21.

Two days later, Lemley allegedly told Mathews, "I literally need, I need to claim my first victim," while discussing targeted acts of violence in Virginia.

"You know we got this situation in Virginia where this is going to be, that opportunity is boundless and the thing is you've got tons of guys who are just in theory should be radicalized enough to know that all you gotta do is start making things go wrong and if Virginia can spiral out to f***ing full blown civil war," Mathews later added.

The pair also discussed ambushing a police officer to obtain tactical gear. "If there's like a PoPo cruiser parked on the street and he doesn't have backup, I can execute him at a whim and just take his stuff ... He literally has zero chance of not being ganked," Lemley said.

Attorneys for Lemley and Mathews did not immediately respond to CBS News' request for comment.

Lemley is standing second from the left while holding a long gun straight in the air, and Bilbrough is kneeling in the center under The Base flag while holding a blade. Federal court exhibit

What is The Base?

Lemley, Mathews and Bilbrough weren't the only members arrested last week. Law enforcement arrested seven total members of The Base, which is described in court documents as a "white supremacist organization" that's discussed "creating a white ethno-state, committing acts of violence against minority communities (including African-Americans and Jewish-Americans) … and ways to make improvised explosive devices."

The youngest defendant in this case, William Bilbrough, appeared to take pride in The Base's stature as a terrorist organization, allegedly making statements that "compared The Base favorably to al-Qaeda." He also allegedly told other Base members that "Isis doesn't compare to us," in reference to the Islamic State of Iraq and Syria.

But prosecutors say Bilbrough began to distance himself from The Base in late 2019 in order to concentrate on his intentions to fight alongside nationalists in Ukraine, even trying to convince other Base members to join him.

At his initial appearance last week, a court appointed attorney told the court that the college student was not a flight risk because he does not own a passport. Bilbrough's attorney told CBS News that after his client's initial appearance, he would argue for the 19-year-old's release, but said he would not comment on the motion.