In Capitol Riot, Communications Between Agencies Hampered Forceful Response

About 90 minutes passed sorting out those needs, with Mr. McCarthy approving the redeployment of 200 troops already at traffic checkpoints and subway stations in the city. More time went by before the soldiers retrieved protective gear and arrived at the Capitol.

In those hours, the mob rioted through the halls and offices of Congress, in the first siege of the building by American citizens. Five people died, including a woman shot by police as she climbed through a smashed door pane outside the House chamber and a police officer fatally injured after being struck in the head with a fire extinguisher.

As rioters stormed the Capitol, the numerous federal and local agencies that police the nation’s capital produced a flood of urgent communications, but they struggled to sort through lines of command and coordinate a forceful response to the assault spiraling beyond their control.

Members of Congress—taken to secure locations—called for help. House Majority Leader Steny Hoyer, a Maryland Democrat, spoke with the state’s Republican governor twice that afternoon, said Gov. Larry Hogan.

“I was actually on the phone with Leader Hoyer, who was pleading with us to send the Guard. He was yelling across the room to [Senate Minority Leader Chuck] Schumer. And they were back and forth, saying we do have the authorization. And I’m saying, ‘I’m telling you, we do not have the authorization,’” Mr. Hogan said at a news conference Thursday.

By late afternoon, the Pentagon, which has to approve National Guard deployments in the capital, authorized the mobilization of 1,100 D.C. National Guard soldiers and 6,200 from six states. Agents from the Federal Bureau of Investigation and the Bureau of Alcohol, Tobacco, Firearms and Explosives also mustered to help regain control.

Pentagon officials defended the response, saying the armed forces have a restricted role in civil law enforcement. “We are not designed to be an emergency response force. By law, the National Guard only is supposed to support local law enforcement,” one defense official said.

Mr. McCarthy, the Army secretary, said at a news conference Wednesday that there was a “bit of confusion” about what resources were needed when Ms. Bowser’s request first arrived. D.C. officials said Ms. Bowser emphasized the need for reinforcements.

In the days before the Jan. 6 rally, local and federal officials took a different tack in their preparations.

Ms. Bowser, in a letter to federal officials Monday, urged a light security footprint for Wednesday’s protests to avoid the type of show of force that inflamed tensions during last year’s racial-justice protests.

Military and defense officials offered assistance and prepared what all sides saw as a sufficient number of D.C. National Guard soldiers—about 340—to perform support duties such as traffic management, military officials said.

The U.S. Capitol Police, which is responsible for security at the Capitol and answers to Congress, twice told the Pentagon that no additional support was needed, according to officials and a Defense Department timeline. Local police generally require permission from Capitol Police to control crowds on the grounds of congressional buildings.

“The general attitude from Capitol Police was: ‘We got this. We do this all time,’” said a U.S. official familiar with the discussions.

Capitol Police didn’t respond to a request for comment Saturday. The agency hasn’t answered multiple questions this week about its response to Wednesday’s assault.

Ahead of the rally, Ashan Benedict, the special agent in charge of ATF’s Washington field office, put a rapid-response unit based an hour away in suburban Virginia on standby. He told senior Justice Department officials that an arson and explosives task force stood at the ready.

“The question mark for everybody was what happens when the speeches are over? Do they just leave to go home? Do they want to move around the city? Do they want to go to the White House? It was hard to say,” said Mr. Benedict. “Ultimately, they went to the Capitol.”

President Trump, in his speech that capped Wednesday’s rally, urged his supporters to march the mile to the Capitol, where a joint session of Congress was due to ratify Democrat Joe Biden’s election as president. When the pro-Trump crowd descended, police were quickly overrun.

Around 12:45 p.m., some marchers were rocking a barrier on the Capitol’s outer security perimeter and soon overturned it, rushing toward the building. Alerted by Capitol Police, ATF agents went to check out reports of potential explosive devices near Republican National Committee headquarters—the first of several types of explosives found in the area that day.

Just blocks from the Capitol, Mr. Benedict said he heard chanting and yelling. “I was standing there while it was escalating,” he said, adding that as he spoke to a Capitol Police captain, the officer’s radio crackled with urgent reports that “the Capitol complex was under duress.”

Around 1 p.m., officers from the city’s Metropolitan Police Department reached the Capitol grounds to assist the Capitol Police.

At 1:18 p.m., police reported “multiple officers injured at the Capitol, west side,” according to radio communications from D.C. area law-enforcement agencies that were recorded by the website OpenMHz.

At 1:41 p.m., “Broken arrow!” said a citywide dispatch, using a term signaling that units are overrun. “Broken arrow!” the radio repeated seconds later.

At 1:53 p.m., the Metropolitan Police Department declared “a breach at the Capitol as well as a riot at the Capitol.”

Five minutes later, Capitol Police formally requested assistance from the ATF and other federal law-enforcement agencies in clearing and securing the building. FBI tactical units, which had earlier been positioned nearby, arrived within minutes.

During these charged minutes, Mayor Bowser called Army Secretary McCarthy requesting National Guard reinforcements, according to the Pentagon. While the Pentagon began assessing the needs, the pressure built.

On a phone call at 2:22 p.m. between Ms. Bowser, police and the Pentagon, Capitol Police Chief Steven Sund described the situation as “dire,” D.C. officials said. Metropolitan police chief Robert Contee asked if Mr. Sund was requesting D.C. National Guard support, and he said “yes,” according to D.C. officials.

Key Communications

12:45 Rioters breach Capitol barricades

1:18 Reports of

multiple officers

injured at the Capitol

1:34 D.C. Mayor

Muriel Bowser

calls Army

Secretary Ryan

McCarthy

for help

1:53 Metropolitan

police declares

“a breach

at the Capitol”

2:22 D.C. officials,

police and Pentagon

discuss the need for

reinforcements

2:40 ATF tactical

teams arrive

on scene

2:49 Reports

of a shooting

inside the

Capitol

3:00 Defense

Department

authorizes 1,100

D.C. guardsmen.

Maryland Gov.

Larry Hogan

mobilizes troopers,

National Guard

3:37 Protesters

cleared from

inside the building

4:00 Hogan is

informed Maryland

guardsmen are not

authorized in D.C.

He receives

authorization

40 minutes later

5:40 D.C.

guardsmen

arrive

on scene

Pentagon officials said they initially raised concerns because they didn’t want to be seen as intervening against what they thought would largely be peaceful protesters. But “it was never optics over safety,” the defense official said.

To D.C. officials, the situation required immediate action. “There was an insurrection under way, yet there was hesitation to send further support,” said John Falcicchio, Ms. Bowser’s chief of staff.

Just after 3 p.m., Mr. Miller verbally approved the deployment of all D.C. National Guardsmen.

After that call, Ms. Bowser’s team started furiously working the phones.

Virginia Gov. Ralph Northam, a Democrat like Ms. Bowser, was holding a routine press conference in Richmond when his top homeland security aide, Brian Moran, received texts about the storming of the Capitol, some 100 miles to the north. Mr. Moran was pulled out of the press conference by Mr. Northam’s chief of staff and informed that Ms. Bowser’s office had called seeking assistance. Within an hour, more than 200 Virginia state troopers were on their way to Washington, said Mr. Moran.

“Absolutely, send them,” Mr. Moran recalled saying. Those troopers, he said, later cleared the inauguration stands on the Capitol’s west side, where Trump supporters had battled police earlier.

Within another hour, House Speaker Nancy Pelosi had made a request for the Virginia National Guard to provide additional assistance, Mr. Moran said.

Maryland Gov. Hogan was participating in a videoconference with Japan’s ambassador to the U.S. when his chief of staff interrupted him around 2:45 p.m. with news that the Capitol was under attack, the governor said. D.C. officials had asked Maryland to send 200 law-enforcement officers through an emergency management assistance compact.

Around 3 p.m., Mr. Hogan mobilized 200 specially trained members of the State Police, according to a spokesman for Mr. Hogan; less than a half-hour later, the governor also authorized the call-up of 150 Maryland National Guard members.

Twice that afternoon, Mr. Hogan spoke by phone with House Majority Leader Hoyer, as they tried to secure Pentagon authorization for the National Guard deployment.

By around 4 p.m., Mr. Hogan said, he learned that Acting Defense Secretary Chris Miller had yet to grant the necessary approval for Guardsmen to enter Washington. “We were repeatedly being told by the National Guard at the national level that we did not have authorization,” Mr. Hogan said.

At 4:41 p.m., Mr. Hogan said he received a phone call from an unfamiliar number. When he answered, he recalled, the caller said: “This is Ryan McCarthy, secretary of the Army, Governor. Can you come as soon as possible?”

Mr. Hogan said he replied: “Yeah, we’ve been waiting. We’re ready.” Mr. Miller had informally assented to the use of National Guard soldiers from outside D.C. minutes earlier, though he didn’t formally approve their deployment until 5:45 p.m., according to the Pentagon.

While National Guard and other assistance was being mobilized, the ATF’s Mr. Benedict called in his tactical teams, which reported their arrival at the Capitol around 2:40 p.m.

Before those teams arrived, Mr. Benedict said he and another senior ATF official, dressed in suits and ties, had gone to the building to find the best path of entry for the teams. As he made his way through the rotunda and elsewhere, he said his eyes stung from the bear spray that protesters had used to overcome police.

“It was absolutely pandemonium inside,” he said. “There were people on the floor in cuffs, and there were people coming down the stairs. There were Capitol Police that were engaged with rioters, and pushing and shoving and getting them in detainment positions.”

Mr. Benedict’s teams and agents had a specific mission to clear certain parts of the building, he said. They took some rioters and handed them down a line of officers, one by one, turning them over to Capitol Police, who put them in temporary restraints, he said.

By 3:37 p.m., authorities had cleared protesters from inside the Capitol building, according to police radio traffic. “The chambers are still sheltering in place. They’ve cleared the rotunda and pushed the protesters outside to the Capitol breezeway,” a citywide dispatch said.

The first D.C. National Guard troops arrived at the Capitol around 5:30 p.m., the Pentagon said, and began to set up a security perimeter around the building.

Several more hours were needed to ensure the area was secure so that members of Congress could return and resume the formal authorization of Mr. Biden’s Electoral College win.

—Gordon Lubold, Erin Ailworth and Dustin Volz contributed to this article.

Write to Scott Calvert at scott.calvert@wsj.com, Nancy A. Youssef at nancy.youssef@wsj.com and Sadie Gurman at sadie.gurman@wsj.com