Four men who were part of a local group with some affiliation with the 'Boogaloo' movement were indicted Friday in federal court for allegedly destroying evidence — some in the form of online chats — connected to indicted murder suspect Steven Carrillo and his May and June 2020 shootings of law enforcement officers.

Carrillo and one alleged accomplice, Robert Justus Jr., were charged last June in connection with the May 29 killing of federal security guard David Patrick Underwood outside the Ronald V. Dellums Federal Building in Oakland during a night of George Floyd protest nearby. Carrillo, a former Air Force Sergeant, was charged with murder and attempted murder, and Justus was charged with aiding and abetting, for his alleged role as driver when the shooting occurred.

Federal investigators quickly found online links between the two men, specifically via a Facebook Group affiliated with the still nascent "Boogaloo" movement — which focuses on the notion of a second Revolutionary War, and members often express contempt for or incite violence toward city, state, and federal law enforcement.

On June 6, a week after the shooting of Underwood and as law enforcement around the Bay Area was hunting for a suspect, Carrillo — a resident of the Santa Cruz mountains — engaged two Santa Cruz County Sheriff's deputies in a shootout, killing one of them, 38-year-old Sgt. Damon Gutzwiller.

Now, as Bay City News reports, investigators say they have evidence that four other men loosely affiliated with Carrillo via a local group called the 1st California Grizzly Scouts, had knowledge of Carrillo's violent intentions, and warned each other before the June 6 shootout to delete messages on WhatsApp and Facebook in order to get rid of such evidence.

Those men have been identified as 29-year-old Jessie Rush of Turlock; 23-year-old Simon Ybarra of Los Gatos; 21-year-old Kenny Miksch of San Lorenzo; and 33-year-old Robert Blancas, a transient.

Federal prosecutors have charged all four men with multiple counts of conspiracy to obstruct justice by destroying phone and internet records, and destruction of records in official proceedings. Rush received an additional charge of obstruction of official proceedings due to his alleged instruction of the others to destroy messages.

The group apparently received a group text from Carrillo on June 6 telling them that he was planning to engage violently with law enforcement. The contents of the messages have not been made public, and it's unclear if they knew about Carrillo's role in the Oakland shooting a week earlier.

A Jessie Rush with a job in security at a Turlock restaurant and a history in the military is listed on LinkedIn. The extremist "Boogaloo" movement has many adherents with military backgrounds who enjoy sharing memes and joking about taking up arms against law enforcement. They employ a term that Carrillo was allegedly using online, "soup bois," to refer jokingly to the "alphabet soup" of federal agencies that they show contempt for, including the FBI, CIA, DEA, ATF, and Homeland Security (HSA).

As Reuters reports, the 1st California Grizzly Scouts are a militia group, and the Department of Justice believes the men had previously "gathered in person for firearms and other training."

The four men all face sentences of up to 20 years in prison, and fines of $250,000 for each conspiracy count. Rush, Miksch and Ybarra made their first court appearances on Friday, and Blancas was making his first appearance on Monday.

Related: Prosecutors Continue Seeking Death Penalty for Both Men Suspected In Oakland Shooting of Federal Guards

Top image: Members of the "boogaloo boys" join other gun rights advocates in front of the State House as pro-gun supporters gather on January 18, 2021 in Richmond, Virginia. The event, which is taking place on the Martin Luther King Jr. holiday, is also known in Richmond as Lobby Day for the tradition of Virginia citizens coming to the capital to petition legislators at the start of the General Assembly session. This year’s event is taking place in the tense atmosphere following the storming of the U.S. Capitol by Trump supporters. (Photo by Spencer Platt/Getty Images)