 The FBI identifying the shooter as 20-year-old Thomas Crooks, who used a semi-automatic AR-style rifle from the roof of a nearby building in an attempt on the former president's life. When Rallygoer was killed, the shooter is dead. Meantime, the Biden administration bolstered security of his presidential candidate's rivals after the assassination attempt on former President Trump. Homeland Security Secretary Alejandro Mayorkas confirms enhanced security for the RNC. At the RNC.