Security officials across local and federal agencies are on heightened alert a day before the inauguration of President-elect Joe Biden, and the hunt for a bombmaker and new IEDs in the D.C. area is high on their radar, the FBI said on Tuesday.
The threat of explosives in the downtown region of the city remains high, as officials continue to search for the suspect who left pipe bombs at both the Republican and Democratic national committee headquarters just blocks away from the Capitol on the same day the building was stormed on Jan. 6.
The bombs did not detonate, but a law enforcement official briefed on the matter told Fox News that catching the suspect, who the FBI believes could be planning similar attacks on Inauguration Day, is a "top priority."
Heightened security concerns come after a mob stormed the Capitol building earlier this month, some intent on harming lawmakers, in a deadly siege that killed five people, including a Capitol police officer.
More than 25,000 National Guardsmen will be squared off around the Capitol's perimeter, with the areas around the White House, other federal buildings and the National Mall on lockdown and armed with a heavy security presence for the big event.
Thousands of federal, state and local law enforcement officials from dozens of states have also joined the ranks in D.C.
This comes as federal investigators continue to probe the possibility of radicalized law enforcement officers who were involved in the Capitol attacks on Jan. 6.
Acting Secretary of Defense Christopher Miller said in a statement Monday that the Department of Defense has not received any intelligence indicating a potential insider threat to the inauguration but added that the department is "leaving no stone unturned in securing the capital."
The FBI continues to monitor "chatter" online about a resurgence of violence as agents comb through nearly 200,000 photos and videos circulating social media and other outlets of the events on that day.
"The Department of Justice is committed, together with our federal, state, and local law enforcement partners, to ensuring a safe and peaceful Inauguration – one that reflects our Nation’s enduring highest values," the DOJ said in a statement Tuesday.
Fox News' Jake Gibson contributed to this report.