United States (U.S.) President Donald Trump has declared a state of emergency in Washington D.C.

The declaration came on the heels of a revelation by the police of three plots to attack the Capitol Building ahead of Joe Biden’s inauguration, including the “largest armed protest in American history”.

It also came as the Federal Bureau of Investigation (FBI) alerted its agents to possible uprisings at capitols in 50 states ahead of Inauguration Day, particularly if Trump is removed from office before Biden enters the White House.

Trump’s declaration allows the Department of Homeland Security and Federal Emergency Management Agency to coordinate with local authorities as Democrats had been furiously demanding.

On Monday night, the new chiefs of Capitol Police told House Democrats they were looking into three separate plans, including one described as “the largest armed protest ever to take place on American soil”.

The protesters plan to involve armed rioters encircling the Capitol and blocking Democrats from entering – killing them if necessary – so that Republicans can take command of government.

They also plan another protest in honor of Ashli Babbitt, the USAF veteran who was shot by a police officer as she tried to clamber into the Speaker’s Lobby during the Trump mob’s siege.

“It was pretty overwhelming,” one Democrat told Huffington Post of the police briefing.

The FBI’s internal memo warned of a group which was calling for the ‘storming’ of state, local and Federal Government buildings, as well as court houses if Trump is removed from office.

The bulletin came to light just as Speaker Nancy Pelosi introduced an article of impeachment accusing Trump of incitement to insurrection, five days after the mob of the president’s supporters stormed the Capitol, leaving five people dead in a futile bid to overturn the general election.

More than 6,000 members of the National Guard were deployed to Washington, DC, over the weekend, with dozens of them standing guard over the Capitol during Monday’s proceedings.

Capitol Police told Congress that it was preparing for up to tens of thousands of Trump supporters arriving in the days ahead, including possible violence to take control of the White House and the Supreme Court.

Working alongside their colleagues in the National Guard, the police are said to have told Democrats that they had agreed on rules of engagement in the eventuality of an armed demonstration.

They do not plan to shoot anyone unless fired at first, but they added that there were exceptions to the rule.

The police urged caution on lawmakers about leaking any specifics to the press because Big Tech had so successfully ‘cut off main communications’ that many could now only learn of plans through traditional media.

One member remarked that the Silicon Valley gagging order on Trump’s supporters “might ultimately save lives”.

But as the Capitol Police expressed confidence it was making sufficient plans to combat any violent uprisings, some lawmakers questioned whether this was the case given the lax security last week.

One Democrat told the police chiefs that there was clear evidence that some in the police department could be ‘in league with the insurrectionists who love to carry their guns.’

“You can’t just let them bypass security and walk right up to Biden and Harris at inauguration,” this lawmaker told HuffPost.

A further area of Democrat speculation surrounded whether the Trump administration was preventing federal law enforcement from lending its expertise to the police.

The member told the HuffPost: “I don’t think anyone has confidence that the folks at the Pentagon, that may or may not even be needed for some of this, or the Department of Homeland Security, where we don’t even know who’s in charge, are going to be cooperative.”

The National Park Service said it would close the Washington Monument and other area facilities beginning today and lasting through January 24.

The Pentagon is also reportedly considering sending as many as 13,000 guardsmen to secure the area on Inauguration Day. Prior to last week’s breach, officials had planned to deploy roughly 7,000 guardsmen.

The hardened-up security plans came after the Department of Defence said it was aware of “further possible threats posed by would-be terrorists in the days up to and including Inauguration Day”, Congressman Jason Crow (D – Colorado) said in a statement Sunday after speaking with Secretary of the Army Ryan McCarthy about security preparations.

The Department of Homeland Security is working with the Defense Department, local DC authorities and inauguration officials to sharpen the law enforcement response in the coming days, including by erecting non-scalable fencing and security checkpoints around Capitol Hill.

“Now that it happened people will take it much more seriously,” a senior DHS official told CNN in reference to last week’s violence. “Now, the planners, they are all going to take it much more seriously.”

Federal and local authorities have faced fierce criticism for their perceived failure to crack down on Wednesday’s insurrection despite evidence that they knew it was coming.

Hundreds of people might face federal charges in the wake of last week’s Capitol breach, DC’s acting US attorney said in an interview with NPR over the weekend, saying a massive, 24-hour-a-day hunt was on to identify suspects and bring charges against them.

In the meantime, DC Mayor Muriel Bowser said she is ‘extremely concerned’ about security on Inauguration Day in a letter to acting DHS Secretary Chad Wolf over the weekend. She wrote that the event ‘will require a very different approach to previous inaugurations given the chaos, injury and death experienced at the US Capitol during the insurrection’.

Biden and Vice President-elect Kamala Harris are set to be sworn in on the west front of the U.S. Capitol on January 20. (Agency report)

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