The court filing listed three individuals by name, Joseph Hackett, Jason Dolan, and William Isaacs, while a fourth person's name was hidden. Three of them have been arrested in recent days, court records show. It was unclear why the fourth person's name was not revealed in the court documents.
This superseding indictment, part of a larger federal government criminal conspiracy case, now includes a total of 16 Oath Keepers. The other 12 co-defendants have pleaded not guilty.
Prosecutors have said in recent weeks that others members of the militia group planned to commit violence and brought firearms into the city.
In a Nov. 9 planning meeting for the attack, the founder of the Oath Keepers, identified as Person One in the filing, referred to the attack as an insurrection, saying "We're gonna be posted outside DC, awaiting the president's orders...We want him to declare an insurrection."