The Department of Justice has added a further four defendants to its conspiracy case against the Oath Keepers over the far-right group's alleged role in the U.S. Capitol riots, a new indictment released Sunday shows.

State of play: Prosecutors have laid criminal charges against at least 19 suspected Oath Keepers or associates in the largest case against any of the extremist groups that took part in the insurrection, per the Washington Post, which obtained the indictment made public by the D.C. District Court.

• These include Jon Ryan Schaffer, 53, the only Oath Keepers member known to have pleaded guilty over the deadly Jan. 6 siege.

What's new: The newly released indictment shows multiple charges were laid against:

• William Isaacs, 21, of Kissimmee, Florida; Jason Dolan, 44, of Wellington, Fla., and Joseph Hackett, 51, of Sarasota, Fla., who appeared before magistrates in the state on Thursday. The name of a fourth defendant was redacted.