The FBI is attempting to pin down a motive after the assassination attempt against former President Donald Trump on Saturday. The shooting took place during a rally in Butler, Pennsylvania.

Donald Trump: “If you want to really see something that’s sad, take a look at what happened” —

Secret Service: “Get down! Get down! Get down!”

Unidentified: “What are we doing? What are we doing?”

A bullet grazed Trump’s ear, leaving him bloodied. Fifty-year-old Corey Comperatore, a volunteer firefighter and spectator, was killed as he attempted to protect his family from the gunfire. Two others are in critical condition. Secret Service fatally shot the gunman, 20-year-old Thomas Matthew Crooks, moments after he fired.

The Justice Department is investigating the shooting as an act of domestic terrorism. Investigators believe Crooks acted alone when he shot an AR-15 toward the rally stage from atop a nearby building, just minutes into Trump’s speech. Some attendees said they spotted the gunman climbing to the roof and attempted to get law enforcement to intervene.

Moments after a bullet grazed Trump’s ear, a photographer from the Associated Press snapped a photo of a bloodied Trump raising his fist with an image of an American flag behind him. Many online commentators are speculating the incident, and the image, would help Trump’s election bid.

President Joe Biden ordered a review of the rally’s security. He addressed the nation from the Oval Office Sunday evening.

President Joe Biden: “There is no place in America for this kind of violence or for any violence ever, period. No exceptions. We can’t allow this violence to be normalized. You know, the political rhetoric in this country has gotten very heated. It’s time to cool it down. And we all have a responsibility to do that. Yes, we have deeply felt, strong disagreements. The stakes in this election are enormously high.”