WASHINGTON Capitol Police briefed Democrats on Monday night about three more potentially gruesome demonstrations planned in the coming days, with one plot to encircle the U.S. Capitol and assassinate Democrats and some Republicans.

On a private call Monday night, new leaders of the Capitol Police told House Democrats they were closely monitoring three separate plans that could pose serious threats to members of Congress as Washington prepares for Democrat Joe Bidens presidential inauguration on Jan. 20.

The first is a demonstration billed as the largest armed protest ever to take place on American soil.

Another is a protest in honor of Ashli Babbitt, the woman killed while trying to climb into the Speakers Lobby during Wednesdays pro-Trump siege of the Capitol.

And another demonstration, which three members said was by far the most concerning plot, would involve insurrectionists forming a perimeter around the Capitol, the White House and the Supreme Court, and then blocking Democrats from entering the Capitol perhaps even killing them so that Republicans could take control of the government.

The members of Congress whom HuffPost spoke to Monday night were extremely concerned by the call.

It was pretty overwhelming, one member said.

Officials on the call warned lawmakers about sharing too much information with the media, saying that divulging specific dates, times and countermeasures could aid the organizers of the plots. HuffPost is not disclosing certain information, such as who appears to be organizing these plots and when they are to take place.

One member was explicit that these groups were trying to get journalists to report on their demonstrations.

Some of their main communications to organize these have been cut off, so theyre purposely trying to get the media to report on this as a way to further disseminate information and to attract additional support for their attacks, this member said.

Democrats were told that the Capitol Police and the National Guard were preparing for potentially tens of thousands of armed protesters coming to Washington and were establishing rules of engagement for warfare. In general, the military and police dont plan to shoot anyone until one of the rioters fires, but there could be exceptions.

Lawmakers were told that the plot to encircle the Capitol also included plans to surround the White House so that no one could harm Trump and the Supreme Court, simply to shut down the courts. The plan to surround the Capitol includes assassinating Democrats as well as Republicans who didnt support Trumps effort to overturn the election and allowing other Republicans to enter the building and control government.

All of these plots may never materialize. The Capitol Police have established a new perimeter with fencing and razor wire, and the National Guard has already been called in to help protect the Capitol and lawmakers.

But while Capitol Police assured members they were prepared for these terrorist plots, there was obvious concern from a number of lawmakers.

One topic of discussion was the need to put every member of Congress through a metal detector before the inauguration. A member on the call told HuffPost that there was an eyes-wide-open realization that Capitol Police needed to take precautions against all these members who were in league with the insurrectionists who love to carry their guns.

You cant just let them bypass security and walk right up to [Joe] Biden and [Kamala] Harris at inauguration, this lawmaker told HuffPost.

Another area of concern was the Trump administrations involvement in tamping down an insurrection. I dont 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 dont even know whos in charge, are going to be cooperative, one member told HuffPost.

One Democrat on the call also raised the issue of security for members coming from their residences to the Capitol, as well as traveling to Washington, given recent confrontations at airports and on flights between some protesters and lawmakers. One member who spoke to HuffPost said the Capitol Police didnt have a satisfactory answer about that concern.

This member mentioned how the briefing had underscored the wisdom of Twitter suspending Trumps account, as well as tens of thousands of accounts associated with the right-wing conspiracy theory QAnon, and said the decision to cut off the social media platform Parler looked a lot smarter given the efforts to recruit armed extremists to come to the nations capital in the coming days.

Its a decision that might ultimately save lives, this member said.

One of the lawmakers who spoke to HuffPost said members of Congress were all experiencing difficult reactions to the storming of the Capitol last week.

Most of us are feeling that, this Democrat said. But we are also feeling that we dont have time to indulge too much of it, that this is not about us, that its about a job thats way bigger than us, and we are just going to suck it up and get through, and well talk about how nutty it is on the other side.

Amanda Terkel and Jennifer Bendery contributed to this report.