Amid growing criticism of a massive security failure, the US secret service pledged on Monday to cooperate in an independent investigation after a gunman was allowed to open fire on Donald Trump.

The 78-year-old former president was injured but survived an assassination attempt at a campaign rally in Pennsylvania on Saturday, a brazen attack that shocked a nation already deeply divided ahead of November’s election.

“The Secret Service is working with all federal, state and local agencies involved to understand what happened, how it happened and how we can prevent an incident like this from ever happening again,” agency director Kimberly Cheatle said in a statement.

“We understand the importance of the independent review that President (Joe) Biden announced yesterday and will fully participate in it,” Cheatle added.

Trump was speaking at a rally in Butler, Pennsylvania, when several bangs rang out.

He grabbed his ear, blood visible on his ear and cheek, and then ducked to the ground as Secret Service agents streamed onto the podium, surrounded him and rushed him to a waiting vehicle.

The shooter and a passerby were killed, two spectators injured.

A recently surfaced video corroborates witnesses’ accounts of calling police and pointing at the gunman as he lay on the roof preparing to open fire, the Washington Post reported Monday.

The shots aimed at Trump were fired 86 seconds after the first audible attempts to warn police, the Post reported, citing an analysis of video clips from the scene.

Biden ordered a comprehensive review of security measures at the rally, as well as at this week’s Republican convention in Milwaukee, Wisconsin, where Trump is expected to be crowned the party’s presidential candidate.

In an interview with NBC on Monday, the president said he felt “safe with the Secret Service,” but added that it was an “open question” whether the shooting at the Trump rally could have been better anticipated.

Biden has also ordered Secret Service protection for independent candidate Robert F. Kennedy Jr. The environmental lawyer and longtime vaccine skeptic has no chance of winning in November, but his candidacy could influence close elections in key swing states.

– Increased risk –

The Secret Service is facing intense scrutiny over how a gunman armed with an assault rifle was able to take up position on a rooftop 500 feet from one of the world’s most protected political figures.

Since Trump will be the star of the convention, Cheatle said the agency is working on enhanced security measures.

The Secret Service is developing plans for major events “to respond to a kinetic security environment and the most current intelligence information,” their statement said.

Trump had previously asked for the Secret Service to protect Kennedy “in light of the current situation in the world.”

“Given the history of the Kennedy family, this is obviously the right thing to do!” Trump wrote on his website Truth Social.

Kennedy’s uncle, President John F. Kennedy, was assassinated in Dallas, Texas, in 1963. Five years later, the candidate’s father, Robert, was shot and killed while campaigning in Los Angeles.

The U.S. Secret Service is responsible for the security of the president, vice president, and former presidents and their families, as well as major election candidates and visiting foreign heads of state.

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