(CNN) The chaotic federal response to the Trump rally Wednesday, which was overwhelmed by rioters who stormed the US Capitol, stood in sharp contrast to the heavily-armed presence of thousands of federal authorities during summer protests in Washington, DC, following the police killing of George Floyd.
Mobs broke through police barricades and rampaged through the Capitol, vandalizing offices and prompting the evacuation of lawmakers just after 2 p.m. ET Wednesday. By dusk, the building was still not secured and a woman had been shot dead.
"Everything. Everything went wrong," one Capitol Police officer on the scene said.
The law enforcement response that allowed a typically heavily secured federal landmark to fall under attack, with rioters breaking through windows and into lawmakers' offices and gathering places, came from a hesitant federal bureaucracy after early assurances from DC and Capitol law enforcement agencies. Agencies that had law enforcement that could help Wednesday waited to be asked.
"It was a mess. Nobody was communicating. No one knew what we were supposed to be doing there," said one federal law enforcement officer who was dispatched to the Capitol.
The primary law enforcement agency tasked with protecting the historic building was the Capitol Police. Spokespeople for the agency have not responded to multiple inquiries from CNN throughout the day.
Justice Department officials were in charge of coordinating the federal agencies and US National Guard response ahead of President Donald Trump's rally near the Washington Monument. Some organizers publicly said they planned to conduct a "wild" march to Capitol Hill as the joint session of Congress met to certify President-elect Joe Biden as the next president.
But agencies were waiting to be asked by other authorities to help -- even as Trump's election protest unraveled.
US Secret Service was the first federal agency deployed when the US Capitol Police asked for assistance from local and federal law enforcement, a USSS official told CNN. When Capitol Police put out the call for assistance, USSS sent additional uniformed division and special agents to Capitol Hill to assist.
"Law enforcement failed to understand what the likelihood of this threat was," CNN law enforcement analyst Jonathan Wackrow, a former USSS agent, said of the day's events, though "no one should be surprised that this was attempted," given Trump attorney Rudy Giuliani's comments at the rally earlier in the day that this should be a "trial by combat."
"There should have been a wall of law enforcement," Wackrow said.
Department of Homeland Security spokesman Alexei Woltornist said the agency was running a "virtual situation room" to track communication between agencies, but was "not tracking any active threats." US Customs and Border Protection, a law enforcement agency under the Department of Homeland Security, had dozens of personnel prepared if needed. Federal Protective Service and Secret Service officers were also sent to the Capitol. Acting Homeland Security Secretary Chad Wolf is on a diplomatic trip in the Middle East this week but making arrangements to return. The Interior Department's US Park Police, which oversees the National Mall and other grounds in the Capitol, also got called in to help.
As for the Justice Department, acting Attorney General Jeffrey Rosen deployed more than 300 agents and officers from the FBI, Bureau of Alcohol, Tobacco, Firearms and Explosives and the US Marshals Service, to assist the Capitol Police. But the Capitol Police had already lost control.
Some of those deployments came almost an hour after the mob put the Capitol into lockdown. Rosen did not issue a public statement condemning the violence until roughly four hours after the riots began.
A longtime DC local police leader, from the Metropolitan Police Department, told CNN, "There is no denying that Capitol Police was extremely overwhelmed today ... I've never seen the Capitol under siege like that."
"By the time the Capitol Police asked for help, the crowd was already inside the building," another federal law enforcement official said.
The Capitol Police reports to leaders of Congress and is separate from law enforcement agencies that are part of the executive branch, the official said. That separation of powers would add to the careful bureaucratic negotiation. In another divide, the Capitol Police operate separately from DC's metropolitan police force, which began enforcing a citywide curfew at 6 p.m. ET.
The first job of the arriving officers Wednesday afternoon was to protect lawmakers and staff who were told to shelter in offices. But the last-minute deployment, with protesters already inside the building, presented special challenges.
FBI and ATF agents -- whose normal job is to be investigators, not to do riot control -- were sent into the Capitol to try to secure the building and eventually to try to clear protesters.
After criticism from Washington, DC, municipal officials over the heavy-handed response during the summer Black Lives Matter protests, federal authorities had a visibly lighter presence for the Trump rally.
Two federal law enforcement officials said Capitol Police assured Justice officials that they were prepared for the rally, particularly since the Capitol grounds are already barricaded in preparation for the Inauguration ceremonies in two weeks.
DC Mayor Muriel Bowser had also written to Rosen and other federal officials demanding that federal agencies not deploy a heavy presence to the city, as they did during the summer, and assuring that Washington's Metropolitan Police, along with a small detachment of National Guard service members, were ready for the day's protests.
"The District of Columbia government is not requesting other federal law enforcement personnel," Bowser wrote, "and discourages any additional deployment without immediate notification to, and consultation with MPD if such plans are underway."
That quickly changed when the crowds surged into the Capitol.
"I think you know the very significant perimeters we established around DC streets, and we're right there to support them and now to enter the building to make sure we have control and maintain control," Bowser said on CNN Wednesday afternoon.
Nearby police departments, including from Fairfax County in Virginia and Montgomery and Prince George's Counties in Maryland, were sending backup of hundreds of officers as the afternoon progressed.
Forces from Prince George's County were in the city and still waiting for direction from the city police late into the afternoon, according to their spokesman, though that was more response than the force had been asked to provide during the Black Lives Matters summer protests, when they were not brought into the city.
National guardsmen were summoned Wednesday from multiple states and began to arrive, after the domestic terrorism began. It was a sharp contrast to how quickly Trump had brought in National Guard and other law enforcement under the executive branch to clear the park in front of the White House of largely peaceful Black Lives Matter protesters this summer. After the harsh disbursement of that crowd, Trump walked across the park and took a photo in front of a church.
"We've going to need the full light of day, the opportunity to have oversight and review to know exactly what occurred," DC Attorney General Karl Racine told CNN Wednesday night, adding that it should be compared to the use of force in Lafayette Square seven months ago. "I have to think that it wasn't unintentional. That it wasn't careless or reckless" to leave the Capitol overwhelmed, Racine said.
One source told CNN Wednesday night Trump had initially resisted deploying the National Guard, and Vice President Mike Pence encouraged the Joint Chiefs Chair to do so more quickly.
Inside the Capitol building as evening fell, officers were still going door to door, searching office by office, checking every closet to make sure the building was secure.
Several police officers had been treated for injuries, a little more than a dozen people had been arrested, pipe bombs found at political party headquarters were safely detonated, and the shooting of a woman on the Capitol grounds who died Wednesday afternoon was under investigation.
This story has been updated with additional information.