The gunman who shot former President Donald Trump at a campaign rally on Saturday was quickly shot and killed by Secret Service agents.

Authorities have not identified the gunman, who had a rifle and opened fire from the roof of a building outside the campaign venue in Butler County, Pennsylvania. Agents returned fire, and photographs later showed law enforcement officers with the man’s body on the roof.

CNN, citing law enforcement sources, said the gunman was a Pennsylvania man about 20 years old. Authorities believe they know his name, but he was not carrying ID.

A Trump supporter said he saw the man with a rifle crawling on top of the roof of a building behind the campaign rally stage. According to the eyewitness, as reported to the BBC, rally-goers outside the event spotted the man “bear crawling” across the roof, carrying a rifle.

The witnesses frantically alerted law enforcement and were surprised when Mr. Trump was not immediately ushered from the stage.

“We’re pointing at the guy, crawling up the roof,” the witness said. “He had a rifle, you could clearly see he had a rifle. I’m thinking to myself, why is Trump still speaking? Why have they not pulled him off the stage?”

The witness said he alerted Secret Service on the roof to the crawling man with the rifle, but Mr. Trump was not removed from the stage.

“The next thing you know, five shots rang out,” the witness said, adding he is “100%” certain the shots came from the rifle of the man crawling across the roof.

Mr. Trump was struck on the right ear but survived and is reported to be “fine.” One rally attendee was killed and two others were critically injured, the Secret Service said.

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