WASHINGTON >> The U.S. Secret Service was under intense scrutiny on Sunday after a gunman managed to evade its agents and open fire on former President Donald Trump at a political rally, with Republican leaders vowing swift investigations and President Joe Biden calling for an independent review.

The gunman, a 20-year-old Pennsylvania man, injured Trump and killed a rally attendee from a rooftop perch around 150 yards (140 m) from the stage where the former president was speaking in Butler, Pennsylvania, near Pittsburgh, officials said.

Trump, 78, who like other former presidents has lifetime protection by the Secret Service, was swarmed by agents who then rushed him away. Agents killed the shooter, identified by the FBI as Thomas Matthew Crooks of Bethel Park, Pennsylvania, and an AR-15-style semiautomatic was recovered near his body, officials said.

Trump says a bullet hit his upper right ear but that he is otherwise doing well and would travel to the Republican National Convention in Milwaukee, where he will receive his party’s presidential nomination.

Mike Johnson, speaker of the Republican-controlled U.S. House of Representatives, said panels in the chamber will call officials from the Secret Service, the Department of Homeland Security and the FBI for hearings.

“The American people deserve to know the truth,” Johnson said.

The House oversight panel called Secret Service Director Kimberly Cheatle to testify on July 22.

The Secret Service, tasked with protecting current and former presidents, is part of the Department of Homeland Security. The department’s Office of the Inspector General is responsible for conducting oversight of Secret Service operations.

A spokesman for the inspector general’s office did not respond to questions about whether it would launch its own inquiry. The FBI said in a statement following the shooting that it would be the lead federal law enforcement agency in the investigation into the shooting.

In a statement, Secret Service spokesman Anthony Guglielmi said the agency had “added protective resources (and) technology (and) capabilities as part of the increased campaign travel tempo.”

Guglielmi denied accusations that the agency had rebuffed requests for more security resources from Trump’s team.

In televised remarks, Biden, 81, said that Trump, as a former president who is the Republicans’ nominee for president in the Nov. 5 election, already receives a heightened level of security.

“I’ve been consistent in my direction of the Secret Service to provide him with every resource, capability and protective measure necessary to ensure his continued safety,” Biden, a Democrat, said.

He said he had “directed an independent review of the national security at yesterday’s rally to assess exactly what happened,” the results of which will be shared with the public.

On Sunday, Democratic Congressman Ritchie Torres said that he and Republican Congressman Mike Lawler are planning to introduce a bill that would call for enhanced security for all presidential candidates.

‘FULL RIFLE KIT’

Paul Eckloff, a former Secret Service agent who retired in 2020, said agents would have surveyed all the rooftops with a line of sight ahead of time.

“This person either concealed themselves until they became a threat, or were not a threat until they revealed their weapons,” said Eckloff.

In the moments after Trump was injured, the former president was quickly surrounded by Secret Service personnel who formed a human shield, while heavily armed agents in body armor and toting rifles also took to the stage and appeared to scan the area for threats.

Trump was whisked by the agents to a black SUV, and taken to a local hospital, according to the campaign.

Trump supporters blasted the Secret Service as having failed to protect the former president. Billionaire Elon Musk called for the agency’s leadership to resign.

“How was a sniper with a full rifle kit allowed to bear crawl onto the closest roof to a presidential nominee,” asked conservative activist Jack Posobiec on social media.

“There will be an intensive review” of the incident and “there’s going to be a massive realignment,” said Joseph LaSorsa, a former Secret Service agent who served on the presidential detail. “This cannot happen.”

SECURING TRUMP RALLIES

During most of Trump’s campaign stops, local police aid the Secret Service in securing the venue. Agents from other agencies within the Department of Homeland Security, such as the Transportation Security Administration, occasionally help.

Many Trump rallies feature thousands of audience members, take place in the open air and last for hours.

Before the event, agents scan the venue for bombs or other threats, and Trump invariably arrives in a fortified motorcade.

Law enforcement officials typically put up barriers as a perimeter, and require all attendees to go through a metal detector to enter the venue. Armed protective agents search all attendees’ bags and even wallets. Many rallygoers are patted down by hand.