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Omar Mir Seddique Mateen (November 16, 1986 - June 12, 2016) was a American mass murderer who killed 49 people and injured 53 others in a gay nightclub in Orlando Florida before being killed in a shootout against the police. Before the shooting, police had called the FBI to check him out due to him claiming he was a part of the military group (ISIS) in 2013 and early 2014. Before the attack, Mateen was a respected security guard working at the bar. At approximately 2:00 a.m. on June 12, 2016, Mateen entered the Pulse nightclub in Orlando, Florida, and began shooting. At 2:22 a.m., he made a 9-1-1 call in which he pledged allegiance to ISIS; referenced Boston Marathon bombers Tamerlan and Dzhokhar Tsarnaev, and mentioned Moner Mohammad Abu Salha, an acquaintance of his who died in a suicide bombing in Syria for the Al-Nusra Front in 2014. According to FBI officials, Mateen made two other 911 calls during the shooting. He also called News 13 of Orlando and identified himself as the nightclub shooter; The Washington Post reported that "he had carried out the Pulse attack for the Islamic State". Mateen took hostages after police arrived and engaged in a gunfight with him. At approximately 5:00 am, police shot and killed Mateen, ending the attack. A total of 49 people were left dead along with Mateen and 53 others were injured. The attack was the deadliest mass shooting by a single gunman in United States history the deadliest incident of violence against LGBT people in U.S. history, and the deadliest terrorist attack in the U.S. since September 11, 2001.