By Andy Sullivan

WASHINGTON (Reuters) -Enrique Tarrio, the former leader of the right-wing group the Proud Boys, and four of his top lieutenants faced new federal charges of seditious conspiracy on Monday for their involvement in the January 6, 2021 attack on the U.S. Capitol, according to a court document.

Federal prosecutors investigating the attack filed the new charges against Tarrio, Dominic Pezzola, Ethan Nordean, Joe Biggs, and Zachary Rehl, according to the document. All five defendants have already pleaded not guilty to other criminal charges related to the attack.

The new indictment accuses the five men of plotting to prevent Congress from certifying Democrat Joe Biden's 2020 presidential victory over incumbent Republican Donald Trump. Trump has made false claims that he lost due to widespread voting fraud.

Prosecutors say Tarrio played a leading role even though he was not in Washington that day, having already been arrested on other charges related to weapons possession.

Three members of another right wing group, the Oath Keepers, have already pleaded guilty to seditious conspiracy charges. Several other members of that group, including leader Elmer Stewart Rhodes, have pleaded not guilty and are due to stand trial later this year.

About 800 people have been charged with taking part in the Capitol riot, with about 250 guilty pleas so far.

(Reporting by Andy Sullivan and Timothy Ahmann; editing by Leslie Adler and Alistair Bell)