Four members of the “Grizzly Scouts” were indicted on Friday for attempting to block an investigation into the shootings of two federal police officers in the Bay Area, a press release from the Department of Justice said. The “Grizzly Scouts” are adherents of the “Boogaloo” movement, a far-right anti-government extremist crusade. The four men—Jessie Alexander Rush, Robert Jesus Blancas, Simon Sage Ybarra and Kenny Matthew Miksch face charges of conspiracy to obstruct justice and destroy records for allegedly erasing messages involving the shootings. Steven Carrillo, a Boogaloo follower, is accused of killing the cops.

The men allegedly chatted on WhatsApp about tactics involved in the murder of police officers, court documents say. One of the four told another member to “factory reset” his phone after he said he was going to engage in a police shootout, according to the statement. Less than an hour later, another of the four allegedly deleted files from a dropbox account related to the shooting. The four also deleted their chat histories, and downloaded a different app to resume talking, the document said. If convicted, they will face up to 20 years in prison.