Governors and other local officials are worried that while high-profile groups like the Proud Boys are encouraging their members to stay away from protests this weekend, other heavily armed and politically motivated extremists could gather in state capitals, leading to violent clashes and creating anxiety for law enforcement trying to prepare, several top-ranking state officials said Friday.

State officials have spent much of the week rushing to secure government buildings and fortify their capitols after an FBI bulletin issued Monday warned that armed far-right extremist groups are planning to march on state capitals this weekend. In response, many states have erected fencing, boarded up windows, closed sites to the public and in some cases declared states of emergency and activated the National Guard.

The U.S. Postal Service also removed collection boxes from areas around several capitols, including in Arizona, Wisconsin and Oregon, fearful they could be used to hide explosives or weapons.

The FBI warning was primarily driven by weeks-old calls by the “boogaloo boys” — a loosely connected group of anti-government advocates who think the country is headed toward civil war — to protest at state capitols Sunday. But in recent days, without clear intelligence about who might show up, state officials said they are bracing for an unruly mix of far-right, white supremacist, gun rights and anti-government extremist groups.

In some cases, officials said, the demonstrators themselves may not get along, adding to tensions that officials said could swiftly escalate into fights among armed individuals, in addition to mob violence aimed at government buildings or leaders.

“These extremist groups, and these right-wing groups, they are a spectrum in terms of ideology and they have different motivations,” Minnesota Attorney General Keith Ellison (D) said. “Some of them are more racist. Some are less racist, and have Black members, but they are still extremists . . . and it’s important that we understand the differences if we are going to protect our government from overthrow.”

In recent days, Enrique Tarrio, leader of the Proud Boys, and the leaders of some other far-right groups have urged their members to stay away from any protests — whether in Washington or state capitals, fearing they are a “trap.”

But not all members of these groups will follow their leaders’ direction and some extremists have no group affiliation, meaning a wide — and perhaps volatile — mix of people could show up.

“If you look what happened on the 6th of January [in Washington], there were a variety of organizations and individuals that showed up, and we expect that to be the same should there be demonstrations at state capitols,” said Charles H. Ramsey, who has served as police chief in Philadelphia and Washington. “There are some groups that are more well-known than others . . . but it’s not going to be limited to just them.”

Law enforcement officials say the nature of the threats remain fairly general. Gathering intelligence on groups and their plans has been complicated with the decision by the nation’s big tech companies to purge the accounts of far-right extremists and the apps they had used to communicate.

“One of the advantages that we had when those fringe groups were available and communicating in the open, with Facebook, Twitter and Parler, is that it was an open-source way to track the flow of protest interest,” said Sgt. Nick Street, a public information officer for the Utah Highway Patrol, which provides security for the state Capitol.

“That was like a nice slow-pitch softball. It was easy to see coming and easy to make contact with,” Street said. “But that was taken away, and no argument here — it’s for the best because of what it could incite and what we witnessed it incite in the events from a week ago.”

Andy Schor, the mayor of Lansing, Mich., said Friday that local elected officials are also finding it difficult to prepare, given the vagueness of many of the threats and the difficulties that officials are encountering trying to track those who plan to demonstrate.

Schor (D) said city police had initially thought that the Proud Boys, a male-chauvinist group with ties to white nationalism, could join alongside supporters of the boogaloo boys movement and the Michigan Militia, a heavily armed local right-wing organization, to protest at the state Capitol on Sunday.

But on a conference call organized by the Voter Protection Program on Friday, Schor said there have been press reports that the “Michigan Militia folks were going to stay away because they were concerned about the Proud Boys and the violence they may perpetrate.”

“So even among some of these extreme groups, you have some standing away because there are others who could be violent,” Schor said.

Conservative activists in some other states are also urging their followers to stay home, claiming the events are a “setup” to frame pro-Trump supporters for violence.

“All conservatives know to stay away from the capitol this weekend,” Alley Waterbury, a pro-Trump supporter who came under fire after she cheered on the events at the U.S. Capitol during a Jan. 6 event in Minnesota, wrote on Facebook.

Don Spencer, president of the Oklahoma 2nd Amendment Association, is urging his members to stay away from protests in his state, even though he strongly believes the presidential election was “stolen by multiple means.” He said the people protesting are engaged in a “scheme to create more instability in an already volatile environment,” which is “nothing more than a ploy to escalate peaceful, law-abiding citizens into a frenzy to damage state and private property.”

But Ramsey, the former police chief, who is now a security consultant, said state leaders should prepare for the possibility that their state capitols could continue to be targets even after President-elect Joe Biden’s inauguration Wednesday.

“There is some information out there that some of these groups are trying to tone things down a bit for [Sunday], and then they may wait and have a surprise attack on state capitols at a later date,” Ramsey said.

On Friday, the leaders of many states were rushing to fortify government buildings while mobilizing additional police officers or National Guard troops to help with security this weekend.

Columbus Mayor Andrew J. Ginther (D) and other state and local officials pleaded with Ohioans to stay home this weekend rather than give protesters who are expected at the Statehouse any oxygen for their causes.

“What hate groups want is confrontation,” Ginther said during a news conference. “Let’s not give it to them.”

Ginther and Columbus Police Chief Thomas Quinlan would not discuss specifics of any threats except to say that hate groups have planned to come to Columbus. Ginther said that the city is staying prepared through Jan. 20 out of an abundance of caution.

Ginther said mayors and other state and local officials have been sharing information about possible protests and hate groups with each other.

“We are planning for the worst-case scenario,” Ginther said.

In California, Gov. Gavin Newsom (D) announced he was sending up to 1,000 National Guard members to protect the state Capitol in Sacramento and also putting temporary fencing around the building.

First-floor windows have been boarded up at Wisconsin’s state Capitol and state employees have been told to work from home through at least the end of January in advance of expected protest activity starting Sunday.

“There is no information about any specific direct threat to Madison or anything in Madison at this point,” said Vic Wahl, the city’s acting police chief. “But because of the national mood, because of the larger national intelligence picture, and out of an abundance of caution, we will continue to maintain an enhanced staffing posture through Inauguration Day.”

Security was also heightened at the Georgia Capitol on Friday, with armed guards and state troopers stationed outside of the gold dome in downtown Atlanta.

“Illegal, un-American activity like we saw last week in Washington, D.C., will not be tolerated in Georgia,” Gov. Brian Kemp (R) said during a news conference earlier this week. “Let me be clear: If you’re coming to Georgia to break the law, it’s better to not come at all.”

At a news conference Friday, Minnesota Gov. Tim Walz (D) and top public safety officials said they have received no credible threats on the state Capitol in St. Paul. But Walz said he worries that heightened security around the Capitol complex could just drive troublemakers to other targets around the Twin Cities.

“If you squeeze the balloon, it comes out somewhere else,” Walz said.

The uncertainty is one reason Schor, the mayor of Lansing, is urging his residents to mostly avoid high-profile government buildings in the coming days.

“For any residents out of walking their dogs, I would walk away from the capitol instead of toward the Capitol,” he said.

LaPlante reported from Salt Lake City. Bailey reported from Minneapolis. Marissa J. Lang in Washington, Annie Gowen in Kansas City, Kathy Lynn Gray in Columbus, Faiz Siddiqui in Sacramento, Jennifer Oldham in Denver, Jimmy Magahern in Phoenix, Haisten Willis in Atlanta, Jeremy Borden in Raleigh, N.C., and Kayla Ruble in Midland, Mich., contributed to this report.