WASHINGTON (AP) — Hours after Joe Biden was declared the winner of the 2020 presidential election, the leader of the Oath Keepers extremist group was discussing how to push President Donald Trump to go further in his fight to cling to power, according to messages shown to jurors Tuesday in his U.S. Capitol attack trial.

Prosecutors used Stewart Rhodes' messages and recordings of him speaking from November 2020 to try to show that he had been working behind the scenes for two months to try to stop the transfer of presidential power before his followers attacked the Capitol on Jan. 6, 2021.

Rhodes and four associates are facing charges of seditious conspiracy for what authorities allege was a detailed, drawn-out plot to keep Biden out of the White House that included putting armed teams on standby outside of Washington. Tuesday was the first full day of testimony in the high-stakes case that's expected to last several weeks.

The five defendants are the first people arrested in the Jan. 6 attack to stand trial for seditious conspiracy — a rarely used Civil War-era charge that can be difficult to prove. Rhodes' attorneys have said their defense will focus on Rhodes' belief that Trump was going to invoke the Insurrection Act and call up the militia to support his bid to stay in power.

The messages were revealed during testimony of an FBI agent investigating the insurrection. In several messages sent around Nov. 7, 2020 — the day that The Associated Press and other news outlets called the election for Biden — Rhodes pressed others to refuse to accept the results and "bend the knee" to what he saw as an illegitimate administration. In one message, Rhodes urged his followers to get their "get your gear squared away" and be "ready to fight."

In another — sent to a group called "FOS" or "Friends of Stone" that included Trump ally Roger Stone — Rhodes urged his fellow Oath Keepers to think of the ways early Americans had resisted the British.

"We are now where the founders were in March, 1775," he wrote. He implored them to "step up and push Trump to finally take decisive action."

"The final defense is us and our rifles," Rhodes wrote to the group. "Trump has one last chance, right now, to stand. But he will need us and our rifles too."

The evening of Nov. 9, Rhodes held a conference call with more than 100 of his followers to discuss the plan. It was secretly recorded by someone on the call and sent to the FBI.

Rhodes urged people on the call to go to Washington and let Trump know that "the people are behind him," according to a recording played to jurors. Rhodes expressed hope that left-wing antifa activists would start clashes because that would give Trump the "reason and rationale for dropping the Insurrection Act."

"So we have a chance to get President Trump to fight as Commander in Chief. If you're going to have a fight, guys, you want to start now while he's still Commander in Chief," Rhodes told the group.

Rhodes said they would have some of their "best men bolstered up outside" — or "quick reaction forces" that he said would be "awaiting the president's orders." It needed to be that way because that gives you "legal cover," Rhodes said on the call.

Rhodes' attorney sought to show that prosecutors are cherry-picking messages from hundreds of chats on his phone. Defense attorney Phillip Linder pressed the FBI agent over whether he ever saw Rhodes encourage anybody to do anything illegal before prosecutors objected to the question.

"All we have is bombastic language," Linder said.

Rhodes' lawyers have said they will argue that their client can't be guilty of seditious conspiracy because all of his actions were in anticipation of orders he expected were coming from Trump under the Insurrection Act. Even though Trump never did, Rhodes' lawyers say he was merely lobbying the president to invoke the law, which gives the president wide discretion to decide when military force is necessary, and what qualifies as military force.

On trial with Rhodes, of Granbury, Texas, are Kelly Meggs, leader of the Florida chapter of the Oath Keepers; Kenneth Harrelson, another Florida Oath Keeper; Thomas Caldwell, a retired U.S. Navy intelligence officer from Virginia, and Jessica Watkins, who led an Ohio militia group.

Prosecutors showed jurors several items found at Caldwell's home, including a notebook with writing about things like "comms" and "lookouts." The FBI agent said that "was all indicative to us of some sort of an operation."

Caldwell's attorney, David Fischer, pressed the agent on whether the government has any witnesses who claim Caldwell had a plan to attack the Capitol on Jan. 6. The agent said it did not.