Documents acquired by NBC News showed that two months prior to the January 6, 2021 riots, an FBI internal report revealed that agents warned that domestic violent extremists were "very willing to take action" in case the 2020 presidential election results were challenged.

On January 6, 2021, supporters of former US President Donald Trump stormed the Capitol in Washington, seeking to prevent certification of Democrat Joe Biden's election victory.

In early August, Trump pleaded not guilty to criminal charges of conspiring to overturn the results of the 2020 election and defraud the American people.

Obtained through a Freedom of Information Act request, the report was based on an "alternative analysis" exercise done by the FBI Boston Field Office that took into account four distinct scenarios.

According to the report, the "most likely" scenario projected by the simulation was that extremists would be eager to act but would be unable to do so due to disunity among groups and pressure from law enforcement.

The groups would be both willing and capable of "a wide range" of violent activities, a second, "less likely" scenario suggested.

The Boston Field Office and the FBI's Intelligence Council, Counterterrorism Division, assisted in the report's preparation, including assistance from an unnamed FBI unit.

Whatever the scenario, the simulation found that extremists' propensity to act in response to a disputed election result would be exacerbated by "underlying grievances related to COVID-19 mitigation measures and racial justice tensions," the report warned.

"Under this alternative analysis, law enforcement preemption and lack of coordination between [domestic violent extremists (DVEs)] would hinder widespread violence, though DVEs engaging in uncoordinated acts of violence remain a threat," it pointed out.

It is noteworthy that federal prosecutors have provided evidence indicating broad collaboration between several far-right groups before the riots. Evidence also revealed that members of those groups expected Trump to guide them in this regard.

A number of the January 6 suspects claim that they stormed the Capitol at Trump's request or at the "invitation" of the former President, who urged his followers before the incident to "fight like hell" and head to the Capitol.

The FBI and other law enforcement agencies have been previously chastised for failing to prepare for possible election-related violence.

In 2021, a Senate report criticized the FBI for failing to issue widespread official intelligence alerts regarding probable violence on that day.

According to a Government Accountability Office assessment from last year, several US government agencies, including the FBI, detected a possibility for violence on that day using open-source data months before the riots.

More than 1,140 arrests have been made in connection with the Capitol attack, according to the US Attorney's office in Washington. Nearly 200 people have pleaded guilty to felony charges while 460 have pleaded guilty to misdemeanors.

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