Concerns are growing over security threats surrounding President-elect Joe Biden’s inauguration next week after the attack on the Capitol rattled the country's confidence and put scrutiny on law enforcement and safety in Washington.

Last week's siege, in which a pro-Trump mob breached the Capitol and was overheard hunting for Vice President Pence and Speaker Nancy Pelosi (D-Calif.), has set off a scramble to avoid a repeat as right-wing groups vow to try to storm the building on Jan. 20 when Biden, lawmakers and former presidents gather.

It’s already led to a domino of announcements: Federal and state officials are beefing up law enforcement and the National Guard presence around Washington, with thousands expected to be deployed in D.C. in the coming days; Trump has declared a state of emergency; and the Secret Service will begin special protections for inaugural events on Wednesday, a week earlier than initially planned.

“There are people plotting to do danger, at least online, and the bottom line is our authorities have to be completely on top of it,” Senate Minority Leader Charles Schumer (D-N.Y.) told reporters.

Sen. Chris Coons (D-Del.), in a recent interview with CBS News, said that the federal government needs to “flood the zone around the Capitol.”

The inauguration will come exactly two weeks after rioters attacked the Capitol, including swarming the West Front, where Biden will receive the Oath of Office, scaling scaffolding and bleachers built for the ceremony.

The leaders of D.C., Maryland and Virginia have pleaded with Americans to stay home and participate in the inauguration virtually, given the dual threats of violence and persistent high levels of COVID-19 cases.

“I want to continue to ask all of our residents to stay away from the downtown, to enjoy the inauguration activities virtually, and let our law enforcement keep peace,” D.C. Mayor Muriel Bowser (D) said on “Good Morning America” on Tuesday.

On Wednesday, AirBNB said that it would cancel and block reservations for the D.C. area during the week of Biden's inauguration.

Biden told reporters Monday that he isn't afraid of taking the oath of office outdoors, as is customary. He also indicated that he had received briefings on the issue, though his transition team did not return a request for more details on what information Biden and his advisers are receiving.

Lawmakers in charge of planning the event are vowing to move forward, even as members privately raise concerns about their own security as threats pour in from across the country.

“We will be swearing in President-elect Biden and Vice President-elect Harris on the West Front of the U.S. Capitol on January 20, 2021. The [Joint Congressional Committee on Inaugural Ceremonies] is working around the clock with our many partners to execute ceremonies that are safe and showcase our determined democracy — to Americans and the world,” the inauguration committee said in a statement.

Members of the committee met this week, officials working on the inauguration were spotted separately doing walkthroughs of the Capitol and briefings are expected on updated security plans in the wake of last week's riot. 

Unlike the Electoral College count the rioters disrupted, the inauguration is considered a National Security Special Event, a designation that will start on Wednesday. A committee spokesperson said it would provide “significant law enforcement and national guard presence as part of the layered security measures within the expanded footprint.”

Acting Homeland Security Secretary Chad Wolf announced plans to move up the security period on Monday, about an hour before abruptly resigning from his position.

But the attack and online chatter from insurrectionist groups is keeping tensions high in the District and putting scrutiny on what was already expected to be a pared-down inauguration due the coronavirus pandemic.

House lawmakers were informed of four specific armed threats against the White House, Capitol and Supreme Court during a call Monday evening. One plot involved thousands of pro-Trump radicals aiming to surround the Capitol in order to prevent Democrats from going, according to Rep. Conor Lamb (D-Pa.), who detailed the threat in an interview on CNN.

The Senate also got a security briefing on the inauguration on Tuesday, and Schumer privately pushed FBI Director Christopher Wray to add participants in the Capitol riot to no-fly lists to try to prevent them from carrying out additional unrest.

On Tuesday afternoon, officials announced that a Chicago man had been arrested and charged with making threats of violence to Biden’s inauguration via a voicemail left for a New Jersey House lawmaker.

Underscoring the depth of concern, Sen. Rob Portman (R-Ohio) issued a forceful statement saying Trump should address the nation and urge his supporters to remain peaceful.

“If our nation experiences additional violence and destruction at the hands of his supporters ... and he does not directly and unambiguously speak out now when threats are known, he will bear responsibility,” Portman said.

The concerns come as Trump, who has been locked out of his beloved Twitter account to prevent him from further inciting violence, has done little to tamp down the tensions. He told reporters Tuesday that he wanted “no violence” but assailed Democrats for trying to impeach him a second time over his role in the riot, saying their efforts are causing “tremendous anger” and endangering the country.

Trump took no responsibility for his rhetoric that incited the mob of angry supporters, calling his words “totally appropriate.”

Meanwhile, Washington is being fortified.

As many as 15,000 National Guard service members will head to the nation’s capital to assist with security ahead of the inauguration.

The Capitol, including nearby office buildings and the Supreme Court, has been surrounded by a seven-foot fence after rioters were quickly able to breach metal barricades that were in place around the building last week. National Guard members are also stationed in and around the Capitol, and metal detectors were placed outside of the House chamber.

Rep. Tim Ryan (D-Ohio), a member of the House Appropriations Committee, said that additional funding was also being allocated.

“We will make sure that Washington, D.C., is secure for the administration of the Oath of Office to Vice President Biden and that everybody there will be safe and secure, and we will have a smooth transition of power,” he told reporters during a conference call.

Under pressure from Bowser, Trump on Monday declared an emergency in the District around the inauguration, allowing additional federal funding to flow to support protection efforts.

It’s not just Washington that is on high alert. The FBI is warning of potential armed protests at state capitols across the country in the days leading up to the inauguration.

Clint Watts, a former FBI official and fellow at the Foreign Policy Research Institute, said he is more worried about attacks on less-protected targets, such as state capitols, rather than the U.S. Capitol because of how extreme the security will be on the Inauguration Day.

“We will not see a major incident. They will lock down the Capitol,” Watts said. “If there’s anybody in the pipeline right now preparing an attack at a state capitol ... you’ve got an FBI that’s absolutely loaded with case leads right now.”

Updated at 11:09 a.m.