The pro-Trump mob that stormed the US Capitol last week aimed to "capture and assassinate elected officials," federal prosecutors said in court documents.
The revelation came in a motion prosecutors filed late Thursday (Friday NZT) in the case against Jacob Chansley, the Arizona man who took part in the insurrection while sporting face paint, no shirt and a furry hat with horns.
The details, tucked into the court papers, shed new light on the seriousness of the Capitol riot. They suggest investigators believe there was a much more organised effort afoot, despite claims from rioters it was a spontaneous outburst of anger over the election and President Donald Trump's loss.
Trump had been repeating baseless claims of election fraud for weeks. Prosecutors say that after Chansley climbed up to the dais where Vice President Mike Pence had been presiding moments earlier, Chansley wrote a threatening note to Pence that said: "It's only a matter of time, justice is coming."
Pence and congressional leaders had been ushered out of the chamber by the Secret Service and US Capitol Police before the rioters stormed into the room.
"Strong evidence, including Chansley's own words and actions at the Capitol, supports that the intent of the Capitol rioters was to capture and assassinate elected officials in the United States Government," prosecutors wrote in their memo urging the judge to keep Chansley behind bars.
The FBI has been investigating whether any of the rioters had plotted to kidnap members of Congress and hold them hostage, focusing particularly on the men seen carrying plastic zip-tie handcuffs and pepper spray.
Prosecutors raised a similar prospect on Friday in the case of a former Air Force officer who they alleged carried plastic zip-tie handcuffs because he intended "to take hostages".
So far, the Justice Department has not publicly released any specific evidence on the plots or explained how the rioters planned to carry them out.
Chansley, who calls himself the "QAnon Shaman" and has long been a fixture at Trump rallies, surrendered to the FBI field office in Phoenix last week. News photos show him at the riot shirtless, with his face painted and wearing a fur hat with horns, carrying a US flag attached to a wooden pole topped with a spear.
QAnon is an apocalyptic and convoluted conspiracy theory spread largely through the internet and promoted by some right-wing extremists. Chansley told investigators he came to the Capitol "at the request of the President that all 'patriots' come to DC on January 6, 2021".
An indictment unsealed on Tuesday in Washington charges him with civil disorder, obstruction of an official proceeding, disorderly conduct in a restricted building, and demonstrating in a Capitol building.
More than 80 people are facing charges stemming from the violence, including more than 40 people in federal court. Dozens more were arrested for violating a curfew that night.
The federal charges brought so far are primarily for crimes such as illegal entry, but prosecutors have said they are weighing more serious charges against at least some of the rioters.
Some were highly-trained ex-military and police. Michael Sherwin, acting US attorney for the District of Columbia, said this week he had organised a group of national security and public corruption prosecutors whose sole focus is to bring sedition charges for the "most heinous acts that occurred in the Capitol".
During a hearing in Texas on Thursday, a prosecutor urged a judge to keep Colonel Larry Rendall Brock Jr locked up, saying the man meant to "take hostages". Brock was arrested on Sunday in Texas after being photographed on the Senate floor during the deadly riot wearing a helmet and heavy vest and carrying plastic zip-tie handcuffs.
"He means to kidnap, restrain, perhaps try, perhaps execute members of the US government," Assistant US Attorney Jay Weimer said, without providing specifics.
Brock's attorney, Brook Antonio II, noted he had only been charged with misdemeanours. Antonio said there was no direct evidence of Brock breaking doors or windows to get into the Capitol, or doing anything violent once he was inside.