The Capitol Police force did not request advance help to secure the building from other federal agencies such as the Department of Homeland Security, according to one senior official.
The bloody chaos inside the US Capitol has come after the police force that protects the legislative complex was overrun by a crowd of President Donald Trump's supporters in what law enforcement officials called a "catastrophic" failure to prepare.
The siege of the Capitol on Wednesday, home to both the US Senate and the House of Representatives, represents one of the gravest security lapses in recent US history, current and former law enforcement officials said, turning one of the most recognisable symbols of American power into a locus of political violence.
Four people died and 52 people have been arrested so far.
While events such as a presidential inauguration involve detailed security plans by numerous security agencies, far less planning went into protecting the joint session of Congress that convened on Wednesday to ratify the results of the 2020 presidential election, the officials said.
That lapse came despite glaring warning signs of potential violence by hardline supporters of President Trump, who are inflamed by Trump's claims of a stolen election and hope to block the inauguration of President-elect Joe Biden.
And security initially was handled almost entirely alone by the US Capitol Police, a 2,000-member force under the control of Congress and dedicated to protecting the 126-acre Capitol grounds.
Warning signs ignored by Capitol police?
Three days before supporters of President Donald Trump rioted at the Capitol, the Pentagon asked the US Capitol Police if it needed National Guard manpower. And as the mob descended on the building on Wednesday, Justice Department leaders reached out to offer up FBI agents. The police turned them down both times, according to senior defense officials and two people familiar with the matter.
Despite plenty of warnings of a possible insurrection and ample resources and time to prepare, the Capitol Police planned only for a free speech demonstration.
Still stinging from the uproar over the violent response by law enforcement to protests last June near the White House, officials also were intent on avoiding any appearance that the federal government was deploying active duty or National Guard troops against Americans.
The Capitol is a short walk from where Trump in a speech railed against the election just before the riot began, calling the vote an "egregious assault on our democracy" and urging his supporters to "walk down to the Capitol" in a "Save America March."
The counting of the electoral votes of the presidential election by Congress, normally a formality, was preceded by weeks of threats in social media that planned pro-Trump protests could descend into violence.
Despite those rumblings of danger, National Guard reinforcements, summoned by the city’s mayor, were not mobilised until more than an hour after protesters had first breached the barricades.
"Security officials may claim the threat posed by a mob of white vigilantes was too far out of mental reach—it was something they could conceive of but not calibrate their plans for. But that’s an indictment, not an excuse," Marc Ambinder wrote in Foreign Policy.
"It’s a failure of the Capitol Police's own leadership, and a failure of the Department of Homeland Security, to take right-wing radical agitation seriously."
NEW: We *finally* have a statement from Capitol Police about what happened yesterday.— Frank Thorp V (@frankthorp) January 7, 2021
USCP says "The USCP had a robust plan established to address anticipated First Amendment activities. "
Also, officer who shot woman in Capitol is on administrative leave. pic.twitter.com/Nzz5CYMIGJ
Too many openings
In stark contrast, those agencies were aggressively deployed by the Trump administration during last summer's police brutality protests in Washington and elsewhere in the United States.
The force's officers are trained to keep protesters off the Capitol's marble outdoor steps, to protect the complex like a citadel.
But there are so many windows and doors in the 19th-century complex that it is difficult to defend them all, said Terrance Gainer, who served as Capitol Police chief and later as the US Senate's Sergeant at Arms, its chief law enforcement officer.
"Once they lost the steps, they lost the doors and windows," Gainer said.
Lack of planning?
As hordes of rioters streamed into the heart of American government, they could be seen on camera roaming freely through the historic halls, swinging from a balcony, rifling through the offices of House Speaker Nancy Pelosi, and even sitting in the chair reserved for the Senate’s presiding officer.
One rioter was captured by a Reuters photographer casually shouldering a large Confederate battle flag as he strode inside the Capitol, a searingly evocative inversion of the failed 1861-1865 insurrection against the American republic by Southern states in an effort to perpetuate slavery.
"I truly had to suspend my disbelief because I didn’t think you could breach the Capitol," said Gainer.
"I have great confidence in the men and women who protect Congress, but there will need to be a full accounting. We’re going to have to have a deep dive into what went wrong."
Lawmakers inside the building blamed a lack of preparation for the historic security breach.
"I think the police did a good job under the circumstances, but there clearly wasn't enough planning," said Representative Vicente Gonzalez, a Texas Democrat.
The long-planned protest, Gonzalez said, called for an "overwhelming display of force" by police.
Failure of intelligence agencies?
Some Democratic members of Congress, worried about the prospects of violence, tried for more than a week to press agencies for information about what they knew about threats or countermeasures, according to one congressional source.
But there was no sign anyone was gathering serious intelligence about possible disturbances or planning to counter them, this source said.
Typically, law enforcement agencies in the American capital spend weeks or months planning for large protests, one former Justice Department official said.
Officials from dozens of agencies, including local police, Capitol Police, the Secret Service and the federal Parks Police, ordinarily gather at the Washington field office of the Federal Bureau of Investigation, the premier national law-enforcement agency, to coordinate their response.
But it's not clear how much of that planning happened for Wednesday’s event.
Bill Bratton, a former New York City police commissioner, told USA TODAY that security response to the violence was "a colossal failure" pointing to "seemingly minimal collaboration" between the various agencies involved.
"Yesterday was truly a day of infamy," he said.
"Based on the fairly straightforward intelligence that thousands of angry people were going to come and show their presence – including groups prone to violence – law enforcement was totally ill-prepared to handle today's incident," said ABC News contributor Brad Garrett, a former FBI special agent.
"This was a phenomenal law enforcement failure."
READ MORE: This is America
'It looked like the Keystone Cops'
A senior federal law enforcement official familiar with the planning to protect other federal sites on Wednesday, including the grounds where Trump spoke, said that he was shocked that the Capitol Police were not better prepared.
"It looked like the Keystone Cops out there," said the official, who spoke on condition of anonymity.
"It should have never happened. We all knew in advance that these people were coming, and the first order of policing is presence."
"The Capitol Police force is essentially a guard force, so it’s hard to understand why they weren’t better prepared."
The challenges of securing the Capitol have been discussed in hearings and in reports for years.
In 2013, Gainer said he proposed a fence, to be called the Capitol Gateway, to stop such a mass assault. It was never built.
"The idea was roundly defeated," he said because members of Congress wanted to protect the public's access and did not want the complex to look like a fortress.
Trump's incitement to crowd behind violence?
Trump on Twitter promised a "wild" event aimed at reversing his loss in last November's election — and appeared to encourage his supporters to act.
"Our country has had enough, and we will not take it anymore," Trump said at Wednesday’s rally. "You have to show strength, and you have to be strong."
The White House did not respond to requests for comment on Trump's role in inspiring violent protests or on the collapse of security at the Capitol.
As Trump returned to the White House, the crowd headed to the Capitol building.
But on Thursday, Capitol Police chief Steven Sund sought to lay blame on Trump, saying siege of US Capitol by Trump supporters was a "criminal riotous behaviour."
He said the violence was unlike any he has seen in his 30 years of experience in law enforcement in the US capital.
Sund said his department had a robust plan established to address anticipated First Amendment activities, adding "14 suspects were arrested in connection with rioting at Capitol Hill."
More than 50 security officers were wounded in the rioting, he said.
Capitol Police overwhelmed?
After a perimetre was quickly breached, Capitol Police officers seemed to be alone in battling the extremists on the building's steps, according to witness accounts and video from the scene.
They were unable to secure all the doors and windows in the sprawling complex.
Protesters surged inside the building, which contains the chambers of both houses of Congress.
Video footage showed Capitol Police overwhelmed by vastly superior numbers of intruders as the crowd grew into the thousands.
Mayor Muriel Bowser had warned of impending violence for weeks, and businesses had closed in anticipation. She requested National Guard help from the Pentagon on December 31, but the Capitol Police turned down the January 3 offer from the Defense Department, according to Kenneth Rapuano, assistant defense secretary for homeland security.
“We asked more than once and the final return that we got on Sunday the 3rd was that they would not be asking DOD for assistance,” he said.
The Justice Department’s offer for FBI support as the protesters grew violent was rejected by the Capitol Police, according to the two people familiar with the matter. They were not authorized to publicly discuss the matter and spoke on condition of anonymity.
By then, it was too late.
Timeline of siege
Two US officials said that Washington city officials had hoped to avoid a militarised response in the days before the protest.
The fear: They were concerned about a repeat of the scenes of the harsh federal response to anti-racism protests that took place across the street from the White House in June.
A US defence official said Washington Mayor Muriel Bowser requested National Guard troops at around 1900 GMT (2 pm local time).
That was about 45 minutes after the rioters had breached the first barricade.
Acting Defense Secretary Chris Miller activated the full DC National Guard at about 1930 GMT (2:30 pm local), the official said.
By then, the Capitol was under lockdown.
In the rotunda, the iconic circular room under the Capitol dome, tear gas masks were being distributed.
Police evacuated Vice President Mike Pence — who was there to preside over the formal counting of the electoral college votes for the election he and Trump lost — and members of the House of Representatives and Senate.
The police used pepper spray and tear gas on the protesters. They tried to barricade doors with furniture but quickly lost the battle.
One woman was shot and killed by Capitol police inside the building, and pipe bombs were recovered at the offices of the Democratic and Republican national committees, Contee said.
He didn't explain what prompted officers to shoot the woman.
Calls to 'rise up' for Trump
While the invasion of the Capitol was unprecedented, there were ample warning signs in the days leading up to the protests.
Many Trump supporters who travelled to the capital shared plans and organised on social media websites such as Parler, a Twitter-like service that has attracted right-wing extremist groups.
Some posters discussed ways to illegally sneak guns into Washington.
In a post on the social media app Parler, the leader of the far-right extremist group the Proud Boys, Enrique Tarrio, promised the group's attendance at Wednesday’s rally.
Tarrio was arrested on Monday in Washington for destruction of property during a protest last month and possession of a firearm magazine.
He pleaded not guilty but was ordered to leave the city on Tuesday.
Joe Biggs, a Proud Boys organiser, said more than 65 members of his group attended the protests but that he did not know whether any of them entered the Capitol building.
He said he advised other Proud Boys to stay inside and avoid confrontations with police.
On Twitter, starting on January 1, there were 1,480 posts from accounts related to the QAnon conspiracy theory movement that referenced Trump’s rally on January 6 and contained references to violence, said a former intelligence official who monitors extremists on social media.
These included calls for "Patriots to Rise Up."
'This is terrorism'
In one popular post on the TikTok video app, a man said that bringing guns to Washington is the "entire reason we’re going."
Neil Trugman, a former Capitol Police intelligence officer, called Wednesday’s invasion of the complex unfathomable.
He said the force generally prepares for much smaller groups under rules designed to allow for maximum expression of free speech rights.
"We're all witnessing something we never imagined," said Trugman, who recently retired as chief of police for Amtrak, the US passenger rail company.
"I'm not sure any chief of police could have handled this any differently."
He blamed Trump for inciting the riot: "This is no longer just a protest. They crossed the line. This is terrorism."