Donald Trump assassination bid 'most significant failure' in decades for Secret Service
The head of the Secret Service has called the assassination attempt on Donald Trump the "most significant operational failure" for the agency in decades.
Kimberly Cheatle said she took "full responsibility" for the lapses in Trump's security, and vowed to "move heaven and earth" to ensure a repeat incident does not occur in the future.
Ms Cheatle made the comments as she was questioned by lawmakers before a congressional hearing on Monday.
"The Secret Service's solemn mission is to protect our nation's leaders. On July 13th, we failed," she said.
Trump narrowly escaped death at a campaign rally in Pennsylvania earlier this month, suffering an injury to his right ear.
Ms Cheatle was repeatedly asked how the gunman - Thomas Matthew Crooks - was able to get so close to Trump, and why the former US president was allowed to take to the stage after local police had identified Crooks as acting in a suspicious manner.
The Secret Service has indicated that Ms Cheatle will not step down from her role at the agency, despite calls for her to resign.
Ms Cheatle appeared to visibly frustrate lawmakers at times during her questioning, saying she was unable to answer questions linked to on-the-day security measures until an ongoing investigation had concluded.
The Secret Service has acknowledged that, prior to Trump's assassination attempt, it had denied requests for increased security at previous events, but that "no assets" were denied for his rally in Pennsylvania.
Crooks was spotted by local police walking around the rally and peering into a rangefinder, before he shot at Trump.
Witnesses described later seeing him climb up onto the roof of a nearby squat manufacturing building, which was within 135 metres of the main stage.
Crooks then opened fire, hitting Trump and killing one spectator. A further two people were left seriously injured and taken to hospital, while Crooks himself was shot dead by authorities.
The attack on Trump was the most serious attempt to assassinate a president or presidential candidate since Ronald Reagan was shot in 1981.
Trump has since accepted the Republican Party's presidential nomination and described his assassination attempt as akin to "taking a bullet for democracy".
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