Capitol police officers in riot gear push back demonstrators who try to break a door of the U.S. Capitol on Wednesday, Jan. 6,…
FILE - Capitol Police in riot gear push back demonstrators at the U.S. Capitol, Jan. 6, 2021, in Washington.

Federal prosecutors late Thursday disclosed fresh details about the far-right Oath Keepers militia group's role in the January 6 assault on the U.S. Capitol by supporters of former President Donald Trump, signaling a widening investigation that could result in charges against additional defendants.  

Twelve members of the Oath Keepers, one of the largest anti-government militias in the United States, have been indicted on conspiracy charges related to the attack, including seven who allegedly formed a military-style "stack" formation to storm the Capitol.  

The rioting left five people dead, including a U.S. Capitol Police officer, and more than 100 other officers injured, triggering one of the largest and most complex criminal investigations in U.S. history.  

Prosecutors had previously said that nearly a dozen members of the Oath Keepers embedded themselves among the rioters to enter the Capitol. But in an overnight court filing, prosecutors highlighted the role of four other "stack members" as well as two other unidentified members of the Oath Keepers.

The six were captured in a photograph included in the court document that shows a group of Oath Keepers standing around their leader, Stewart Rhodes, outside the Capitol for what prosecutors described as "an after action gathering" around 4 p.m. on January 6.

Federal prosecutors say this photo shows members of the far-right Oath Keepers group standing near their leader, Stewart Rhodes, for what prosecutors describe as "an after action gathering" following the storming of the US Capitol, Jan. 6, 2021.

The filing suggests that prosecutors almost certainly know the identities of the half-dozen members of the Oath Keepers who have not been charged. But whether all or any of the members will eventually face prosecution remains uncertain. It's possible that some of them are cooperating with prosecutors in a bid to avoid lengthy prison terms, a former law enforcement official said. 

The 12 charged Oath Keepers face five criminal counts related to the breach of the Capitol. If convicted, they could face up to 20 years in prison.  

Rhodes, who is referred to as "Person One" in court documents, remains under investigation but has not been charged. He has denied any wrongdoing. Last month he told a Republican rally in Texas that he might go to jail "not for anything I did but for made-up crimes." 

FILE - In this Sunday, June 25, 2017 file photo, Stewart Rhodes, founder of the citizen militia group known as the Oath Keepers…
Oath Keepers Founder Feeling the Heat from US Prosecutors
Former Army paratrooper and Yale Law School graduate Stewart Rhodes predicts he might land behind bars because of his role in January 6 riot at US Capitol

Jordan Strauss, a managing director at Kroll, an international risk management consultancy, said the latest court filing provides evidence of a widening conspiracy.  

"The filings so far have demonstrated that so-called 'stack' participants were, in fact, working in close cooperation with one another, and possibly with leaders of the organization," said Strauss, who previously served as a federal prosecutor and trial attorney.  

Membership in extremist groups such as the Oath Keepers is not a crime. But FBI Director Christopher Wray warned last month that the federal authorities "will not tolerate violent agitators and extremists who use the guise of First Amendment-protected activity to incite violence and wreak havoc."  

The latest disclosure came in a government brief opposing the pretrial release of Joshua James, one of the 12 members of the Oath Keepers indicted in the conspiracy case. 

James, 33, was not part of the "stack" that stormed the Capitol. But prosecutors say James, a fellow Oath Keeper named Roberto Minuta and others stormed the building about half an hour later.  

The latest court document includes a screen shot of surveillance video showing James, Minuta and other militia members riding to the Capitol in two allegedly stolen golf carts.  

Federal prosecutors say this image from surveillance video shows militia members riding to the Capitol in allegedly stolen golf carts as protesters storm the US Capitol on Jan. 6, 2021.

James "shouted directions while his driver and codefendant (Minuta) made it clear what they were doing: 'Patriots storming the Capitol building … word is they got in the building … let's go,'" prosecutors wrote. 

As Minuta sped toward the building, James punched the Capitol address into his phone and "audibly" gave directions to his driver, "aiding them in their endeavor to storm the Capitol," according to the filing. 

Approximately 800 Trump supporters entered the Capitol on January 6, according to the U.S. Capitol Police.

FILE - A mob of supporters of President Donald Trump fight with members of law enforcement at a door they broke open as they storm the Capitol Building in Washington, Jan. 6, 2021.

A running tally of the Capitol charges by the George Washington University Program on Extremism shows that 369 people have been federally charged in the three months since the attack.  

The vast majority have no known ties to extremist groups. But among the charged rioters are 28 members of the far-right Proud Boys, 13 members of the Oath Keepers, and five members of the Three Percenters, another militia group, according to the George Washington University tally. 

In recent weeks, prosecutors have zeroed in on these groups as they have sought to identify and prosecute key players in the conspiracy.

The indictment against the 12 members of the Oath Keepers alleges that the group began plotting to overturn the results of the November election shortly after the vote.  

In December, Rhodes published two open letters on the Oath Keepers website, calling on Trump to invoke the Insurrection Act to "stop the steal" and prevent President-elect Joe Biden from taking office. And two days before the assault on the Capitol, Rhodes issued a "call to action," writing that it was "CRITICAL that all patriots who can be in DC get to DC to stand tall in support of President Trump's fight to defeat the enemies foreign and domestic." 

The Insurrection Act allows the president to use active-duty military and the National Guard during civil unrest. The Oath Keepers believe the act allows the president to "call up the militia," including "patriotic Americans of military age." 

Throughout the conspiracy, members of the Oath Keepers allegedly used a variety of platforms such as the encrypted messaging app Signal to communicate, coordinate and plan the attack, according to prosecutors.