US National Guard troops are preparing for potential homemade bomb threats amid fears pro-Donald Trump supporters may attack the Capitol again on Inauguration Day.
Thousands of members of the military reserve component have been deployed and are being forced to sleep on the floor of the building in between shifts.
The heavily armed troops have been warned individuals may use improvised explosive devices amid growing tensions ahead of Joe Biden being sworn in on December 20, two Guardsmen told Politico.
Bombs were planted at the Republican National Committee (RNC) and Democratic National Committee (DNC headquarters during the Capitol Hill riot last week, with those responsible yet to be arrested.
The FBI have appealed to people living in the area for any photos or video footage which may help their investigations, residents told Politico.
Striking images show hundreds of troops resting at the Capitol and in between shifts providing round the clock security at the Washington complex they have been treated to takeaway pizzas.
It comes as US law enforcement bosses warned of a plot in which 4,000 armed protesters could descend on Washington in the coming days, encircling the Capitol once again and potentially assassinating politicians.
It was one of three extremist plots picked up by security services that were detailed in a phone call between US Capitol Police and Democrat members of Congress, according to politicians who were on the call, reported The Times.
It also emerged that the FBI had warned extremists were planning for "war" the day before the storming of the Capitol on January 6.
In a video posted to the White House Twitter page on Wednesday evening, President Trump had condemned last week's violence but the previous day had warned Biden to "be careful what you wish for".
"It's causing tremendous anger and division and pain far greater than most people will ever understand, which is very dangerous for the USA, especially at this very tender time," Trump said before he was impeached for a second time.
Some have taken this as possibly a reference to the potential for further unrest.
The National Guard, who were called in the midst of the riot, were deployed again on Wednesday morning to patrol the Capitol in the coming days.
Up to 20,000 guardsmen could be stationed there by the inauguration on request of the DC Metropolitan Police Department and other authorities.
Anti-climb steel fences have also been erected.
Right-wing extremist group Patriot Actions for America is reportedly organising a violent rally at the Capitol on Saturday (January 16), according to an unclassified Secret Service intelligence bulletin obtained by Politico.
