Federal law enforcement officials have advised police agencies in state capitals to increase their security posture at statehouses around the country following the riot at the US Capitol, law enforcement sources told ABC News.

The concern, the sources said, is an emboldened right-wing that considered Wednesday a success and may next turn to locations in closer to home.

Like the U.S. Capitol, statehouses are often backdrops for demonstrations that law enforcement officials now fear could turn violent.

“The safety of the Massachusetts State House, its employees and its neighbors is of utmost importance. As we witness the events in Washington, DC and across the nation, we are aware of the need to ensure the safety of this building and those who work within it. We continually assess our security needs and will adjust as necessary,” said Massachusetts Gov. Charlie Baker, Senate President Karen Spilka and House Speaker Ronald Mariano in a joint statement.

Across the country in Washington state, Gov. Jay Inslee activated the National Guard to patrol the Capitol Campus when the state legislature convenes Monday.

“As legislators begin their work on behalf of the people of the state of Washington, we must do whatever we can to ensure that they can do that work without fear, intimidation or harassment. The actions we saw in both Washington, D.C. and Olympia earlier this week were completely unacceptable and will not be repeated in our state capital again,” Inslee said.

Security was also increased around the statehouse in Maryland, Gov. Larry Hogan said.

“Maryland State Police as well as Maryland Capitol Police, some of which you see around here, have increased security around the Maryland State House complex, since there’s been a number of incidents at state capitols and governor’s mansions around the country,” Hogan said.

-ABC News' Aaron Katersky and Josh Margolin

Florida authorities say on Friday night they arrested one of the alleged Capitol rioters who was seen in a viral photograph carrying Speaker Nancy Pelosi’s lectern through the halls.

Adam Johnson, 36, of Parrish, Florida, is being held in Pinellas County Jail and charges are pending after federal marshals picked him up, according to arrest records.

Army Secretary Ryan McCarthy said Friday the Army will soon determine whether to allow Guardsmen to be armed for the inauguration based on a review of threat intelligence.

"We'll be looking at the intelligence and make a determination over the next day or so," McCarthy told the Associated Press. "It's just going to require us to get better intel, and then we'll have to make a risk assessment."

"The Secretary of the Army, in concert with Federal and Metropolitan leadership and D.C. National Guard continue to assess the security environment in the District of Columbia," an Army official told ABC News.

"As part of the standard mission analysis, we evaluate mission requirements based on requests, and it can include looking into the force posture level and the standing rules for the use of force. The Army is a planning organization and this a standard part of mission analysis," the official added.

- ABC News' Luis Martinez

After an hours-long phone call earlier Friday with the entire Democratic caucus, House Speaker Nancy Pelosi in a new statement is walking a fine line on next steps and remaining noncommittal on moving forward with impeachment.

Pelosi said it's still Democrats' hope that Trump will "immediately resign."

"But if he does not, I have instructed the Rules Committee to be prepared to move forward with Congressman Jamie Raskin’s 25th Amendment legislation and a motion for impeachment. Accordingly, the House will preserve every option – including the 25th Amendment, a motion to impeach or a privileged resolution for impeachment," she said in the statement.

This comes after nearly 160 Democrats have signed on to legislation in support of a single article of impeachment against the president -- which it is expected that they still plan to introduce as early as Monday -- but Pelosi does not definitively say she will support it or that the chamber will move forward with impeachment.

- ABC News' Mariam Khan and Benjamin Siegel

House Speaker Nancy Pelosi, in a new letter to Democrats on Saturday, asked members to prepare to return to Washington this week -- another signal that the House could take up and pass the impeachment article to the Senate after it is formally introduced on Monday.

Pelosi thanked fellow Democratic representatives for speaking with her on a conference call Friday and said she was taking their considerations into account. She did not specifically mention voting on impeachment in the letter, though.

"Since that call, I have received scores of communications from Members expressing your views about how we go forward and regarding a strong presence of our Caucus in the Capitol," she wrote. "Over the last few days, I have discussed your views with Constitutional lawyers, both inside and outside the Congress, to consider the parliamentary and constitutional options available to us."

"From what I have heard from Members, and from the deluge that I have received from the public, it is clear that, once again, the Times Have Found Us to save our democracy," Pelosi added in the letter. "We will be proceeding with meetings with Members and Constitutional experts and others. I continue to welcome your comments. I urge you to be prepared to return to Washington this week."

While Democrats are hopeful Republicans will back their effort, none have come out and said they would back the charge as drafted.

Pelosi said at a press conference on Thursday, "If the Vice President and Cabinet do not act [on the 25th Amendment], the Congress may be prepared to move forward with impeachment."

Some Democrats planned to connect with Republican colleagues this weekend to gauge their support and encourage them to back the effort.

-ABC News' Benjamin Siegel