Four men suspected of being leaders of the far-right Proud Boys have been implicated in the U.S. Capitol riots, according to a new indictment unsealed on Friday, which reveals how federal authorities believe community members plotted and carried out a concerted attack to keep Congress from certifying President Joe Biden’s electoral victory.

At least 19 leaders, members, or supporters of the neo-fascist Proud Boys have been charged with crimes linked to the Jan. 6 riots in federal court. According to the new indictment, the Proud Boys had a much larger contingent in Washington, with over 60 users “participating in” an encrypted messaging channel built a day before the riots for party members.

After the arrest of the group’s top leader, Enrique Tarrio, in Washington, the Proud Boys abandoned an earlier channel and formed the new “Boots on the Ground” channel. Tarrio was arrested on Jan. 4 and charged with vandalizing a Black Lives Matter banner during a rally in December at a historic Black church. He was told he couldn’t reach the District of Columbia.

Tarrio has not been charged in connection with the riots, but his title as the chairman of the Proud Boys is stated in the current indictment.

Two of the four suspects charged in the new indictment, Ethan Nordean and Joseph Biggs, were arrested several weeks ago on separate but similar charges. Zachary Rehl and Charles Donohoe are also included in the latest indictment.

All four defendants are accused of plotting to prevent Congress from certifying the Electoral College vote. The indictment also contains charges of obstructing an official proceeding, obstructing law enforcement during a civil disturbance, and disorderly behavior.

Nordean, 30, of Auburn, Washington, was the president of his Proud Boys chapter and a member of the organization’s national “Elders Council.” Biggs, 37, is a self-described Proud Boys organizer from Ormond Beach, Florida. According to the indictment, Rehl, 35, of Philadelphia, and Donohoe, 33, of North Carolina, are presidents of their respective Proud Boys chapters.

Biggs’ lawyer declined to comment. Attorneys for the other three men did not respond to messages left for them on Friday.

Proud Boys members have regularly participated in street battles with antifascist activists at marches and demonstrations, describing themselves as a politically incorrect men’s club for “Western chauvinists.” Gavin McInnes, a Vice Media co-founder who created the Proud Boys in 2016, filed a lawsuit against the Southern Poverty Law Center for identifying the organization as a hate group.

On Jan. 6, the Proud Boys assembled at the Washington Monument about 10 a.m. and marched to the Capitol before then-President Donald Trump finished speaking to thousands of supporters outside the White House.

A group of Proud Boys accompanied a crowd of people who smashed barriers at a pedestrian entrance to the Capitol grounds two hours later, shortly before Congress held a joint session to certify the election results, according to the indictment. After the crowd shattered windows and forced open doors, many Proud Boys stormed the Capitol building itself.

According to the indictment, Donohoe declared on the “Boots on the Ground” channel at 3:38 p.m. that he and others were “regrouping with a second force” as some rioters started to flee the Capitol.

“This was more than just a march. During a recent hearing for Nordean’s lawsuit, Assistant US Attorney Jason McCullough said, “This was an extraordinary assault on our institutions of government.”

The Proud Boys allegedly arranged for members to communicate using unique frequencies on Baofeng radios, according to prosecutors. The Chinese-made devices can be configured to work on hundreds of frequencies, rendering eavesdropping difficult.

According to the new indictment, after Tarrio’s arrest, Donohoe expressed fear that their encrypted communications could be “compromised” if police searched the group chairman’s phone. According to the indictment, Donohoe warned members that they may be facing “gang charges” in a Jan. 4 post on a newly formed channel, and wrote, “Stop all immediately.”

He went on to say, “This comes from the top.”

According to the indictment, Biggs posted on the “Boots on the Field” channel the day before the riots that the group had a “plan” for the night before and the day of the riots.

A federal judge in Nordean’s case accused prosecutors of reversing their arguments that he ordered Proud Boys representatives to break up into smaller groups and directed a “strategic plan” to breach the Capitol.

On March 3, U.S. District Judge Beryl Howell said, “That’s a far cry from what I heard at the hearing today.”

Nordean was actively involved in “pre-planning” for the events of January 6, according to Howell, and he and other Proud Boys “were obviously prepared for a violent confrontation” on that day. She did, however, state the evidence that Nordean ordered other Proud Boys members to break into the building is “bad to say the least,” and she released him from custody before his trial.

On Friday, Howell ordered Christopher Worrell, a member of the Proud Boys, to be held in federal detention awaiting his conviction on riot-related charges. Worrell allegedly flew to Washington and coordinated with the Proud Boys in the run-up to the siege, according to prosecutors.

In a court filing, prosecutors wrote, “Worrell advanced, concealed himself behind a wooden platform and other protesters, and fired the gel at the line of police, wearing protective clothing and armed with a canister of pepper spray gel branded as 67 times more potent than hot sauce.”

Defense attorney John Pierce claimed that his client was simply in the crowd to exercise his right to free expression and wasn’t aiming at police.

“He’s a seasoned combatant. Pierce said, “He loves his country.”