By Zachary Cohen, Shimon Prokupecz and Whitney Wild

WASHINGTON, D.C. (CNN/WJZ) — The unprecedented second impeachment trial of former President Donald Trump will take place under extraordinary security inside the US Capitol — a physical reminder that federal officials still believe threats to lawmakers and federal buildings are possible more than a month after the January 6 insurrection.

Members of the National Guard still patrol the exterior of the Capitol complex — in some cases along 8-foot, non-scalable fences topped by razor wire.

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Within the halls of the building, all nine House Democratic impeachment managers are flanked by a security detail as they walk to votes and take meetings around the Capitol. The managers were also assigned a security detail during last year’s impeachment trial.

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In addition, enhanced security measures around the US Capitol will remain in place due to the ongoing potential for violence by domestic extremists, in part due to the heightened political tension surrounding the trial itself, sources familiar with the plans told CNN. Access to the Senate will also be tightly regulated, as it was during Trump’s first impeachment trial.

Federal law enforcement officials say they are not currently tracking any “specific and credible” threats to the Capitol surrounding the Senate impeachment trial, which is scheduled to begin on Tuesday, but relevant agencies, including the FBI and the Department of Homeland Security, remain on high alert. They’re using all the tools at their disposal to avoid the security and intelligence failures that occurred leading up to the January 6 Capitol attack.

UNITED STATES – February 10: A banner that reads convict or be complicit hangs over a bridge on North Capitol Street on the second day of former President Donald Trump’s second impeachment trial at the U.S. Capitol in Washington on Wednesday, Feb. 10, 2021. Trump is charged with incitement of insurrection after his supporters stormed the Capitol in an attempt to overturn Novembers election result. (Photo by Caroline Brehman/CQ-Roll Call, Inc via Getty Images)

The FBI continues to conduct surveillance on a number of people in the US, in cases where there is enough probable cause to do so — monitoring for any signs that they are planning something specific around the impeachment trial and in the weeks that follow, according to a law enforcement official.

Law enforcement officials have also reached out to some of the suspects in an effort to discourage them from facilitating unrest or violence, the official said.

As part of that effort, officials are closely tracking threats against individual members of Congress, which have continued to mount in recent weeks. Ensuring the safety of lawmakers in Washington and as they travel back to their home states has become a particular area of focus, sources have told CNN.

Security precautions in place

Multiple congressional sources familiar with Capitol security operations told CNN that lawmakers have not been briefed on any imminent threats surrounding the impeachment trial but noted enhanced security precautions will be left in place out of an abundance of caution, and additional steps have been taken to protect lawmakers with prominent roles in the proceedings.

House Speaker Nancy Pelosi told Democrats last week that additional security has been provided for lawmakers when they are traveling.

“The Sergeant at Arms (SAA) and U.S. Capitol Police (USCP) are partnering with the Transportation Security Administration, Federal Air Marshal Service and Washington Metropolitan Airports Authority to increase security for Members while traveling to and from Washington,” she wrote in a letter to members.

“Among other steps, USCP will be stationed at BWI, IAD, DCA and Union Station to provide extra security on days with increased Member travel,” Pelosi added, using acronyms for the airports that serve DC. “Given the serious and ongoing security threats facing Members and the Congress, it is clear that there is a need for an emergency supplemental funding bill to meet institutional security needs.”

A TSA spokesperson declined to comment on what additional security measures would be afforded lawmakers while traveling to and from Washington.

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Nationwide, detainment memos filed by federal prosecutors show officials are treating the threat of organized violence as not only possible, but also likely. Prosecutors are urging judges to consider the potential for similar events when deciding whether riot defendants should remain behind bars. Friday, Department of Justice attorneys argued that a Seattle member of the right-wing extremist group the Proud Boys should stay in custody.

“There is no reason to believe that Defendant, or any of his Proud Boy associates, are any more interested in ‘complacency,’ or any less interested in fomenting rebellion, than they were on January 5,” prosecutors wrote. “If nothing else, the events of January 6, 2021, have exposed the size and determination of right-wing fringe groups in the United States, and their willingness to place themselves and others in danger to further their political ideology. Releasing Defendant to rejoin their fold and plan their next attack poses a potentially catastrophic risk of danger to the community.”

The likelihood of planned gatherings or protests in the District throughout the week is minimal.

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Michael Litterst, a spokesman for the National Park Service, told CNN in an email that the agency was reviewing only two applications for permitted events in DC this week: one a free speech demonstration calling for Trump to be convicted and another to protest the political situation in Myanmar.

A spokesman for the Metropolitan Police Department said the agency hasn’t issued any permits for events.

But law enforcement officials are acutely aware that extremists could be inspired by rhetoric from lawmakers or online narratives that emerge during the trial and in the weeks that follow.

Those concerns echo warnings issued by the Department of Homeland Security in a threat bulletin last month, which officials say reflects a clear shift in how the agency is prioritizing the issue of domestic extremism under President Joe Biden in a way the Trump administration did not.

“If you’ve been to the Capitol in the last three weeks it’s like an armed fortress here. And so I’m not personally worried about my physical security here and about the security of the building and the institution right now,” Rep. Elissa Slotkin, chair of the House Intelligence Counter Terrorism Subcommittee, told reporters last week when asked about concerns related to impeachment.

Another major event for US Capitol Police

This week also marks another major event for the US Capitol Police since the rally-turned-riot at the Capitol on January 6. In a YouTube video posted Friday, US Capitol Police acting Chief Yogananda Pittman said the department is working side by side with the National Guard during upcoming congressional events.

“We have taken steps to ensure the operational tempo and the posture of the department conforms with the available intelligence,” Pittman said in the video.

A sign reading “Police Line Do Not Cross” on temporary security fencing around the U.S. Capitol in Washington, D.C., U.S., on Wednesday, Feb. 10, 2021. House Democrats used searing video footage from last months deadly rampage at the U.S. Capitol to begin Donald Trumps second impeachment trial on a dramatic note, yet the prosecution remains far from winning enough GOP votes to convict the former president. Photographer: Stefani Reynolds/Bloomberg via Getty Images

US Capitol Police spokeswoman Eva Malecki did not immediately respond to CNN’s request for comment regarding security around the impeachment trial.

The department approaches the trial with officers still nursing visible and invisible injuries. According to Pittman, 125 officers were assaulted during the riot, leaving 70 injured. She noted some officers within the department are still struggling. Sources within US Capitol Police told CNN that following the riot they are physically and mentally exhausted and worried that leadership is not equipped to usher the department through the heightened threat environment.

While several congressional sources agreed that they are not overwhelmingly concerned about threats specifically tied to the trial, there are varying opinions about how to address security around the Capitol and for lawmakers long term.

Federal and state officials have previously made clear that the increased security posture in the nation’s capital will extend into March due to several concerns, including possible threats around the impeachment trial.

Capitol security officials are also looking at what the security posture should look like months after the trial, as Republicans and Democrats are already raising concerns about some of the precautions becoming permanent.

The final assessment made by retired Lt Gen. Russel Honore, a former Army commander who has been tasked with conducting an independent review of security measures around the Capitol, will be factored into that decision, according to Pelosi, who has largely deflected when asked about changes to the Capitol security posture after the trial.

Members of the National Guard walk through temporary security fencing at the U.S. Capitol in Washington, D.C., U.S., on Wednesday, Feb. 10, 2021. House Democrats used searing video footage from last months deadly rampage at the U.S. Capitol to begin Donald Trumps second impeachment trial on a dramatic note, yet the prosecution remains far from winning enough GOP votes to convict the former president. Photographer: Stefani Reynolds/Bloomberg via Getty Images

Asked about security around the impeachment trial, including additional protection for members and their families, a congressional aide echoed what Pelosi and her staff have said in recent weeks, telling CNN: “Honore is looking into member security and will make recommendations about this that the House will review.”

“I will say it will be interesting to know what the plan is longer term,” Slotkin, a Democrat from Michigan, said last week. “You know, the Michigan National Guard is back participating in protecting the Capitol right now, our National Guardsmen will not be here and should not be here forever. These gates and fences should not be here forever. So do we have a security situation that’s better than January 6, especially given the hell that the Capitol Police has gone through as an organization since then? That’s definitely something I’m interested in.”

Slotkin also told reporters her committee will be focused on addressing the threat of domestic terrorism “writ large, not just against the Capitol, which of course is symbolic and important, but also in our local communities.”

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