Omar Mateen
Omar Mateen committed the Pulse Nightclub shooting on June 12, 2016, in Orlando, Florida, killing 49 and injuring 53. During and after the attack, Mateen stated that he was loyal to ISIS and that the recent killing of an ISIS commander motivated his attack. Though Mateen had some history of behavioral issues, he had previously been screened for signs of radicalization and cleared by the FBI. Mateen was shot and killed during the nightclub attack.