The Department of Homeland Security inspector general has opened an investigation into the Secret Service and their handling of the assassination attempt of former President Donald Trump.

Trump was wounded in the shooting in Butler County, Pennsylvania. One rally attendee was killed and two others were injured.

The inspector general’s website was updated Wednesday morning with the notice that the investigation is to “Evaluate the United States Secret Service’s (Secret Service) process for securing former President Trump’s July 13, 2024 campaign event.”

According to the inspector general’s account on the social media platform X, the office’s job is to “provide independent oversight of @DHSgov.”

No date was provided when the investigation was started, the AP reported.

President Joe Biden called for an independent review of what led to the shooting of Trump by Thomas Crooks, 20.

Crooks was able to get within 135 meters of the former president with an AR-style gun, despite warnings from rally attendees.

On Tuesday, officials said there was a threat to Trump from Iran, which necessitated additional security for the former president, the AP reported.

Secret Service Director Kim Cheatle said the agency will work with investigators as well as congressional committees to examine what happened and to ensure it doesn’t happen again.

Cheatle told CNN that the Secret Service was “solely responsible” for the security at the rally.

“At that particular site, we divided up areas of responsibility, but the Secret Service is totally responsible for the design and implementation and the execution of the site,” the director told CNN.

Earlier she had told ABC News that local law enforcement was responsible for the building where Crooks was perched.

“What I was trying to stress was that we just divided up areas of responsibility, and they provided support to those areas of responsibility,” Cheatle said, adding the organization “couldn’t do our job without them.”

The FBI is also investigating, CNN reported.

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Trump attempted assassination BUTLER, PENNSYLVANIA - JULY 13: Republican presidential candidate, former U.S. President Donald Trump arrives for a rally at Butler Farm Show Inc. on July 13, 2024 in Butler, Pennsylvania. Shortly after, shots rang out and Trump slumped before being whisked away by Secret Service with injuries visible to the side of his head. Butler County district attorney Richard Goldinger said the shooter and one audience member are dead and another was injured. (Photo by Jeff Swensen/Getty Images) (Jeff Swensen/Getty Images)

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