Watch Live: Secret Service director testifies about Trump shooting

Washington — Secret Service Director Kimberly Cheatle is testifying before the House Oversight and Accountability Committee about the attempted assassination of former President Donald Trump , where she is facing mounting frustration from Republicans and Democrats alike over her unwillingness to answer questions about the security failures at the rally in Butler, Pennsylvania.

Cheatle told lawmakers that the attack is the "most significant operational failure" for the Secret Service in decades, and repeatedly said she takes full responsibility for the security lapses. But her promise for accountability did little to quiet the calls for her to resign, and at least one Democrat on the committee, Rep. Ro Khanna of California, joined Republicans in calling for her to step down.

"You cannot go leading a Secret Service agency when there is an assassination attempt on a presidential candidate," he said. "I would say that about anyone."

Across the heated hearing, Cheatle fielded questions as to why Trump was allowed to take the stage at the rally when the shooter, identified by the FBI as 20-year-old Thomas Matthew Crooks , had been deemed suspicious by law enforcement, and defended the number of agents assigned to protect the former president at the campaign event.

She repeatedly cited the FBI's ongoing criminal investigation into the assassination attempt when declining to discuss the specifics of the gunman's actions leading up to the attack.

Cheatle also told lawmakers that she believes she is the "best person to lead the Secret Service at this time," but acknowledged that the agency failed in its mission to protect the nation's leaders.

"We must learn what happened and I will move heaven and earth to ensure an incident like July 13th does not happen again," she said.

Here's the latest from the hearing:

Democratic Rep. Jared Moskowitz likens Cheatle's testimony to Ivy League presidents

Rep. Jared Moskowitz, a Democrat from Florida, invoked a disastrous December congressional hearing on antisemitism that led to the resignations of two of the three university presidents who testified, and said Cheatle's performance is similar to theirs.

"That's how this is going for you," he said. "This is where this is heading."

Moskowitz said many Democrats, Republicans and independents will find it "unacceptable" that members of Congress are getting fewer answers from Cheatle than she gave ABC News in an interview after the assassination attempt.

"A president was almost assassinated live on television, not just for Americans but for the world to see," he said.

Cheatle declined to unequivocally say whether she would have resigned if Trump were killed by the gunman, and instead said, "I think that I've admitted that I've taken accountability and will take responsibility."

Cheatle says Secret Service was made aware of suspicious person 2 to 5 times before shooting

Cheatle said the Secret Service, who worked with local law enforcement at the rally, had been told about a suspicious person two to five times before the shots were fired.

"From what I have been able to discern, somewhere between two and five times there was some sort of communication about a suspicious person," she said.

Rep. Byron Donalds, a Florida Republican, criticized Cheatle for her leadership, calling it "gross incompetence."

In response to an opportunity from Rep. Dan Goldman, a New York Democrat, to explain her unwillingness to answer lawmakers' questions, Cheatle said she is answering them to the best of her ability.

Nancy Mace: "You're full of s--t today"

Rep. Nancy Mace, a Republican from South Carolina, devoted her time to a series of yes-or-no questions and quickly grew frustrated as Cheatle repeatedly declined to answer accordingly. Mace objected to the Secret Service's failure to comply with demands for documents and other information from the committee.

"On July 15, this committee sent you a list of demands of information that we wanted," Mace said. "Has the Secret Service provided this committee a complete list of all law enforcement personnel that were there that day? Have you done that? Have you provided a list to the Oversight Committee?"

"I'd have to get back to you on that," Cheatle answered.

"That is a no. Have you provided all audio and video recordings in your possession to this committee, as we asked on July 15?" Mace asked.

"I'd have to get back to you on that," Cheatle repeated.

"That is a no. You're full of s--t today. You're just being completely dishonest," Mace said, her voice rising. The comment prompted another lawmaker to urge Mace to "preserve decorum."

Mace continued: "You are being dishonest or lying. You're being dishonest here with this committee, these are important questions that the American people want answers to, and you're just dodging and talking about it in generalities. We had to subpoena you to be here, and you won't even answer the questions. We've asked you repeatedly to answer our questions. This isn't hard."

Cheatle lays out steps the Secret Service has taken since assassination attempt

The Secret Service chief said that following the assassination attempt, the agency made adjustments to the inside of the perimeter at the Republican National Convention in Milwaukee, Wisconsin, last week and to the security posture for protectees in the Washington, D.C., area.

She said on the heels of Mr. Biden's decision to end his campaign for reelection Sunday, the Secret Service also made adjustments to Harris' detail and is prepared for an eventual Democratic vice presidential nominee. Harris has said she is seeking the party's presidential nomination.

"It just shows how dynamic the environment is that this agency works in every day," Cheatle said.

Cheatle says teams were dispatched to interview Crooks after he was identified as suspicious

In an exchange with Rep. Andy Biggs, an Arizona Republican, Cheatle revealed that law enforcement teams were sent to identify and interview Crooks after he was deemed suspicious. She did not provide any additional details, including when the team was sent to make contact with him.

"At a number of our protected sites, there are suspicious individuals that are identified all the time," she said. "It doesn't necessarily mean that they constitute a threat."

Cheatle says internal investigation will take 60 days, which Ocasio-Cortez calls "unacceptable"

Cheatle told Oversight Committee members that she expects the Secret Service's internal investigation into the assassination attempt to be done in 60 days.

That timeline was swiftly criticized by Rep. Alexandria Ocasio-Cortez of New York, who called it "unacceptable."

"This is not theater. This is not about jockeying. This is about the safety of some of the most highly targeted and valued targets internationally and domestically in the United States of America," she said. "The idea that a report will be finalized in 60 days, let alone prior to any actionable decisions that would be made, is simply not acceptable."

Cheatle, toward the end of the line of questioning, told Ocasio-Cortez: "I want to assure you and everyone on this committee that I'm not waiting for a report to take action. We have been conducting analysis all along and we have been adding additional features to our security details since this incident occurred."

Frustration with Cheatle crosses party lines

The Oversight Committee includes some of Trump's most vocal defenders on Capitol Hill, but it's not just his supporters who are exasperated with Cheatle's answers.

Democrats like Khanna and Connolly have shown frustration with the Secret Service chief as well. GOP Rep. Jim Jordan of Ohio said Cheatle hadn't answered a single question from Comer, Raskin or himself.

"How long do we have to wait before you can give us credible answers?" Republican Rep. Pete Sessions of Texas said. "You've been there 28 years. You've had a few days to build and draw your own analysis of this. You should understand the entire process."

Sessions later grew angry, demanding Cheatle to tell lawmakers what went wrong at the rally.

"Don't try and play a shell game with us," he said. "Do you have the ability to effectively, as the director of this agency, to understand what went wrong?"

Democratic Rep. Ro Khanna: "You need to resign"

Khanna, a California Democrat, raised the attempted assassination of former President Ronald Reagan in 1981 and the response by the head of the Secret Service at the time, Stuart Knight.

"I just don't think this is partisan. If you have an assassination attempt on a president, a former president, or a candidate, you need to resign," he said. "That's what Stuart Knight did. He was a Republican appointee."

Khanna said he hopes Cheatle will consider leaving her post at the agency.

"You cannot go leading a Secret Service agency when there is an assassination attempt on a presidential candidate," he said. "I would say that about anyone."

Cheatle bats down conspiracy theories about shooting

Rep. Raja Krishnamoorthi, an Illinois Democrat, asked Cheatle to address some conspiracy theories that have emerged in the wake of the attack. She told him that the shooting was not staged, it was not a conspiracy by high-ranking government officials and it was not perpetrated by a foreign state or entity.

Cheatle also indicated that the Secret Service did not believe there was a threat to Trump that would've led them to pause the rally.

Agents would "never bring the former president out if there was a threat that had been identified," she said.

Cheatle said she did not personally review the security plan for Trump's rally, but there are multiple people who look at and sign off on them.

"If we determine through the course of our investigation that someone or people need to be held accountable, we will do so," she said.

Democrat Gerry Connolly gets exasperated asking Cheatle about the ubiquity of guns

Democratic Rep. Gerry Connolly of Virginia grew frustrated as he questioned Cheatle about how the Secret Service's job is impacted by guns in the hands of members of the public.

"Does the ubiquity of guns make your job easier or more difficult today?" he asked Cheatle repeatedly.

The Secret Service chief declined to directly answer Connolly's question, saying instead she understands that the American people have a Second Amendment right to bear arms. Her response angered Connolly further.

"You're not making my job easier in assessing your qualifications in continuing on as director," he said. "Please answer the question."

Connolly also accused Cheatle of giving an evasive answer to his question, which he said is "not a hard one."

"We almost lost a presidential candidate the other day," he said, noting that the gunman was able to access his father's rifle and get close to Trump.

Connolly continued: "You're not willing to answer that question and you wonder why we might have a lack of confidence in your continued ability to direct this agency."

Cheatle eventually conceded that "it's the environment that the Secret Service works in every day."

Cheatle cites FBI investigation in declining to discuss specifics about gunman

Cheatle has pointed to the FBI's ongoing criminal investigation several times in declining to discuss the specifics of the gunman's actions in the lead-up to the shooting.

Under questioning from GOP Rep. Glenn Grothman of Wisconsin, Cheatle demurred when asked about how the gunman got onto the roof and other details about his actions.

"I'm unable to answer details of exactly how the individual accessed the roof at this time," she said. "I'd like to be able to answer those questions. The FBI is still conducting an investigation.

Cheatle: "I am the best person to lead the Secret Service at this time"

Cheatle defended her job performance at the helm of the Secret Service and said she believes she was selected for the role by Mr. Biden because of her 27 years of experience working for the agency.

"I think that I am the best person to lead the Secret Service at this time," she told Rep. Virginia Foxx, a North Carolina Republican.

Cheatle has faced calls to resign in the wake of the attack on Trump.

Cheatle faces questions over Iranian threat to Trump

Rep. Mike Turner, the chairman of the House Intelligence Committee, focused his questions on an Iranian plot against Trump that was detected by U.S. intelligence. There were no ties between the assassination attempt and any foreign or domestic accomplice.

Cheatle told Turner she read intelligence of the generalized threat to Trump by Iran and was briefed on the specific plot by the Iranians. Asked by Turner whether she believes the protection plan was sufficient to protect Trump, Cheatle said she believes it was.

Still, she acknowledged that there were "gaps and a failure that day," which allowed Crooks to have access to the rooftop.

Cheatle says she's spoken with the counter-sniper who killed the gunman

In response to questions from GOP Rep. Jim Jordan of Ohio, Cheatle said he has briefed Mr. Biden and Vice President Kamala Harris about the attempted assassination, and also spoke to the Secret Service counter-sniper who killed Crooks.

The Secret Service chief did not reveal any details about her conversation with the sniper. She said she has not spoken with first lady Jill Biden or White House communications staff.

Cheatle says there was a "sufficient number" of Secret Service agents assigned to Trump rally

Cheatle told Comer during his round of questioning that there were a "sufficient number" of agents who were assigned to protect Trump at the Butler rally on July 13.

"The agents that were assigned to former President Trump are Secret Service agents that provide close protection to him and that is what was actual on that day," she said.

Cheatle also said that the assets requested for the July 13 rally in Butler were given, and for the event, "there were no requests that were denied."

"There are a number of ways that threats and risks can be mitigated with a number of different assets, whether that be through personnel or technology or other resources," she said.

Cheatle confirmed that Crooks, the gunman, was identified as suspicious, but noted that if Trump's detail had been informed that there was a threat, agents would not have allowed the former president to go out on stage.

"That is what we do and that is who we are," she said.

Those identified as suspicious have to be investigated, Cheatle said. She also told lawmakers that the FBI informed the Secret Service that Crooks flew a drone near the rally site before the event.

"I accept responsibility for this tragedy," she said. "We are going to look into how this happened and we are going to take corrective action to ensure that it never happens again."