Former President Donald Trump was the target of an apparent assassination attempt Saturday at a Pennsylvania rally, days before he was to accept the Republican nomination for a third time. A barrage of gunfire set off panic, and a bloodied Trump, who said he was shot in the ear, was surrounded by Secret Service and hurried to his SUV as he pumped his fist in a show of defiance.

Trump’s campaign said the presumptive GOP nominee was doing “fine” after the shooting, which he said pierced the upper part of his right ear.

“I knew immediately that something was wrong in that I heard a whizzing sound, shots, and immediately felt the bullet ripping through the skin. Much bleeding took place,” he wrote on his social media site.

The FBI early Sunday identified the shooter as Thomas Matthew Crooks, 20, of Bethel Park, Pennsylvania. The agency said the investigation remains active and ongoing.

Secret Service agents fatally shot Crooks, who attacked from an elevated position outside the rally venue at a farm show in Butler, Pennsylvania, the agency said.

One attendee was killed and two spectators were critically injured, authorities said. All were identified as men.

The attack was the most serious attempt to assassinate a president or presidential candidate since Ronald Reagan was shot in 1981. It drew new attention to concerns about political violence in a deeply polarized U.S. less than four months before the presidential election. And it could alter the tenor and security posture at the Republican National Convention, which will begin Monday in Milwaukee.

Organizers said the convention would proceed as planned.

Trump flew to New Jersey after visiting a local Pennsylvania hospital, landing shortly after midnight at Newark Liberty International Airport. Video posted by an aide showed the former president deplaning his private jet flanked by U.S. Secret Service agents and heavily armed members of the agency’s counter assault team, an unusually visible show of force by his protective detail.

President Joe Biden, who is running against Trump, was briefed on the incident and spoke to Trump several hours after the shooting, the White House said.

Biden planned to return to Washington early, cutting short a weekend at his beach home in Rehoboth Beach, Delaware.

Many Republicans quickly blamed the violence on Biden and his allies, arguing that sustained attacks on Trump as a threat to democracy have created a toxic environment. They pointed in particular to a comment Biden made to donors on July 8, saying “it’s time to put Trump in the bullseye.”

Officials said members of the U.S. Secret Service counterassault team killed the shooter. The heavily armed tactical team travels everywhere with the president and major party nominees and is meant to confront any active threats while other agents focus on safeguarding and evacuating the person at the center of protection.

Law enforcement recovered an AR-style rifle at the scene, according to a third person familiar with the matter who spoke on condition of anonymity to discuss the ongoing investigation.