• U.S. Secret Service Director Kimberly Cheatle resigned amid outrage over her agency's failure to prevent the attempted assassination of former President Donald Trump at a campaign rally.
• Cheatle's resignation came a day after a House committee hearing blasted her for the Secret Service's actions leading up to Trump's July 13 rally in Butler Township, Pennsylvania.
• President Joe Biden said he planned to appoint a new director "soon."

U.S. Secret Service Director Kimberly Cheatle resigned Tuesday amid widespread outrage over her agency's failure to prevent the attempted assassination of former President Donald Trump at a Pennsylvania campaign rally earlier this month.

Cheatle's resignation, which was first reported by NBC News citing sources, came a day after she was blasted by members of a House committee at a hearing on the Secret Service's actions leading up to Trump's July 13 rally in Butler Township.

Cheatle rejected calls at that hearing to resign, saying she was the best-qualified person to head the Secret Service, which is responsible for protecting the president, vice president, their family members and leading presidential candidates.

The director angered members of the House Oversight and Accountability Committee by refusing to answer many questions about the Secret Service's actions surrounding Trump's rally, where the Republican presidential nominee narrowly avoided being killed by 20-year-old gunman Thomas Crooks. One man died in the shooting, while two others were critically injured.

On Tuesday, Cheatle in a letter wrote to Secret Service staff, "In light of recent events, it is with a heavy heart that, I have made the difficult decision to step down as your Director."

"The Secret Service's solemn mission is to protect our nation's leaders and financial infrastructure. On July 13th, we fell short on that mission," said Cheatle, who served in the agency for nearly 30 years.

"The scrutiny over the last week has been intense and will continue to remain as our operational tempo increases," she wrote. "As your Director, I take full responsibility for the security lapse."

Homeland Security Secretary Alejandro Mayorkas appointed Secret Service Deputy Director Ronald Rowe to serve as acting director for the agency until a permanent director is selected by President Joe Biden.

Biden in a statement thanked Cheatle for "her decades of public service," and said, "As a leader, it takes honor, courage, and incredible integrity to take full responsibility for an organization tasked with one of the most challenging jobs in public service."

Biden also said he plans to appoint a new Secret Service director "soon."

Trump, in a social media post responding to Cheatle's resignation, wrote, "The Biden/Harris Administration did not properly protect me, and I was forced to take a bullet for Democracy. IT WAS MY GREAT HONOR TO DO SO!"

The chairman of the House Oversight Committee, in a statement, said that Cheatle's departure would not stop that panel's demand for "more accountability" from the Secret Service.

"The Secret Service has a no-fail mission yet it failed historically on Director Cheatle's watch," said Rep. James Comer, R-Ky., the chairman who had demanded her resignation, along with the panel's ranking Democrat, Rep. Jamie Raskin of Maryland, and other committee members.

"At yesterday's Oversight Committee hearing, Director Cheatle instilled no confidence that she has the ability to ensure the Secret Service can meet its protective mission," Comer said.

"While Director Cheatle's resignation is a step toward accountability, we need a full review of how these security failures happened so that we can prevent them going forward."

The criticism of Cheatle centers on the Secret Service's failure to secure a roof that Crooks used as a sniper's post to shoot at Trump and rally attendees, among other lapses.

The building whose roof Crooks positioned himself on is about 150 yards from the stage where Trump was speaking, and had a clear line of sight and fire to that stage.

The Secret Service did not extend its security perimeter for the rally to include the complex that included that building, instead leaving it up to local law enforcement officials to secure that area.

Secret Service agents also allowed Trump to take the stage and begin speaking after receiving a report from local police that a suspicious person had been seen at the event. That person ended up being Crooks, who was killed by a Secret Service sniper after he fired multiple rounds at Trump, and after the sniper had already seen Crooks on the roof.

Cheatle was widely mocked after the shooting for rationalizing the decision to not put a law enforcement sniper on the roof that Crooks climbed up to while being seen by rally attendees who warned police about what he was doing.

Cheatle in an ABC News interview noted that the roof was sloped at its highest point.

"There's a safety factor that would be considered there that we wouldn't want to put somebody up on a sloped roof," she told ABC News. "And so, the decision was made to secure the building, from inside."

This weekend, the Secret Service admitted that on the heels of the shooting it had incorrectly stated that the agency had not rejected requests from Trump's campaign for enhanced security for him.

The shooting, the most serious assassination attempt against a U.S. president in more than 40 years, came after the Secret Service was informed of intelligence that Trump was the target of an Iranian assassination plot. Crooks has not been linked to Iran.

The Secret Service in recent years has been the target of criticism for a series of scandals and missteps.