WASHINGTON — Cassidy Hutchinson, who was an aide to former White House chief of staff Mark Meadows, delivered explosive testimony Tuesday to the House select committee investigating the Jan. 6, 2021, insurrection, offering startling details on the activities of President Donald Trump and those around him before the attack on the U.S. Capitol and on the deadly day itself.

Trump’s temper was a big part of this hearing.

Trump was so “irate” that he wasn’t being driven to the Capitol following his speech on the Ellipse on Jan. 6, 2021, that he attempted to grab the steering wheel of his limousine and lunged at a member of his Secret Service detail, former White House aide Cassidy Hutchinson testified in a House hearing Tuesday, citing the account of a senior-ranking colleague.

“I’m the f---ing president! Take me up to the Capitol now!” Hutchinson, a former aide to White House chief of staff Mark Meadows, quoted Trump as saying in testimony to the House select committee. She also described an outburst by Trump at his former attorney general in which he threw dishes, leaving ketchup streaming down the wall.

Hutchinson recalled that her boss, Meadows, told her days before the Jan. 6 insurrection that “things might get real, real bad” at the Capitol on that day. Her testimony is part of previously unscheduled hearing by the House select committee focused on her first-hand experiences in the presence of Meadows and Trump.

Rep. Bennie Thompson, D-Miss., the committee chairman, opened the hearing by saying it would focus on “details of what transpired in the office of the White House chief of staff just steps from the Oval Office as the threats of violence became clear and indeed violence ultimately descended on the Capitol in the attack on American democracy.”

Hutchinson’s comment came after a White House meeting involving Trump attorney Rudy Giuliani, Hutchinson said. Giuliani, as he was leaving the White House on Jan. 2, asked her if she was “excited” for Jan. 6, she said. When she asked what was happening on that day, Hutchinson testified that Giuliani told her, “We’re going to the Capitol.”

When Hutchinson conveyed Giuliani’s comments to Meadows, she testified, he told her, “There’s a lot going on,” before delivering the ominous warning about things potentially getting “real, real bad.”

“That evening was the first moment I remember feeling scared and nervous for what could happen on Jan. 6,” Hutchinson testified. “And I had a deeper concern for what was happening with the planning aspects of it.”

Hutchinson’s descriptions of her former boss, Mark Meadows, paint an unflattering picture of someone who lacked leadership and often took the path of least resistance in response to the former president’s actions. Hutchinson described Meadows as scrolling through his phone, unresponsive, and negligent during pivotal moments on Jan. 6 in particular.

The hearing added evidence that some people in the crowd on Jan. 6 were armed, including with assault rifles. The committee played police radio transmissions describing people carrying weapons, as well as testimony from Hutchinson describing Trump’s urging the Secret Service to remove metal detectors rather than turn away people with weapons.

The new evidence comes on top of multiple people charged in the riot who were found with loaded guns. The Justice Department has also accused the Oath Keepers of stashing weapons just outside D.C. At a hearing last July, former Capitol Police officer Harry Dunn testified to seeing the outline of a gun on one rioter’s hip.

Hutchinson opened her testimony to the Jan. 6 committee with a reminder that she has been a committed Republican before this moment. Before working for Trump, she testified she was an aide on Capitol Hill, working for Republican Whip Steve Scalise of Louisiana and Sen. Ted Cruz, R-Texas.

She then sought out a job in the White House and worked there, rising in responsibilities, from 2019 through January 2021. The committee displayed photos to demonstrate how close Hutchinson was to Republicans. One showed her smiling with Scalise. Another showed her walking at the White House with Rep. Jim Jordan, R-Ohio, as well as Meadows.

Committee Vice Chairwoman Liz Cheney, R-Wyo., made the point in introducing Hutchinson, noting that a “significant number of Republicans” have testified, and she is the latest.

Thompson said he and Cheney called this hearing because they had obtained new information about what Trump and his top aides were doing in the critical hours leading up to and during the Capitol attack.

“It hasn’t always been easy to get that information because the same people who drove the former president’s pressure campaign to overturn the election are now trying to cover up the truth about Jan. 6,” Thompson said. “But thanks to the courage of certain individuals, the truth won’t be buried. The American people won’t be left in the dark. Our witness today, Cassidy Hutchinson, has embodied that courage.”

Cheney noted that Hutchinson had already sat for four taped interviews with the committee and that she was a familiar face on Capitol Hill because she had played a prominent role in the White House’s legislative affairs office.

“We will begin to examine evidence bearing on what President Trump and members of the White House staff knew about the prospect for violence on January 6th even before that violence began,” Cheney said.

The point Cheney keeps making at these hearings: The people providing some of the most damning testimony are all Republicans, and most were handpicked or appointed by Trump. Trump and his orbit have tried to undercut the committee’s work by saying it is a partisan witch hunt, led by Democrats and Republicans who despise Trump. But it’s more challenging to attack the taped, or live, testimony from Trump’s own aides and family members, and that has grown to annoy Trump.

Alyssa Farah, a former White House communications director, sought to push back against anticipated arguments from Republicans that Cassidy Hutchinson was merely a “low-level staffer.”

“She was anything but,” Farah said during an appearance on CNN ahead of the expected testimony from the Meadows aide.

“She was so plugged in that I would often go to her as the White House communications director to get intel on the president’s schedule, his movements, things we were considering as far as events,” Farah said. “She also was on a first-name basis with most members of congressional leadership. She would text with them. So she’s seen everything. She’s been in so many rooms. She was always on Air Force One.”

Tuesday’s hearing was unexpected because the Jan. 6 panel had previously signaled it would not hold any more hearings until July, after it evaluated additional evidence.

The panel’s last hearing, on Thursday, featured testimony from former Justice Department officials describing Trump’s efforts to undo the 2020 election results. The committee also identified five Republican lawmakers who allegedly sought pardons.

In a break with its past five hearings this month, the panel provided no advance confirmation about the witness list Tuesday and members did not appear on television beforehand.