At around 2am on Sunday morning, a gunman armed with an AR-15-style assault rifle and a handgun opened fire at a crowded gay dance club in Orlando, Florida. At least 50 people were killed and 53 wounded, making the attack the deadliest mass shooting in American history.
Authorities have identified the gunman as 29-year-old Omar Siddiqui Mateen, and said he was killed in a shootout with police inside the club at around 5am. Details about Mateen are still emerging, but here's what we know so far:
-Mateen is a US citizen born to Afghan parents. He was living in Port St. Lucie, a city about a two-hour drive southeast of Orlando on Florida's Atlantic coast.
-The Islamic State's Amaq news agency said on Sunday afternoon that Mateen was a "fighter" for the militant group, but it's still unclear whether the group was in direct contact with Mateen or if he was merely inspired by them.
Related: Here's Everything We Know So Far About the Florida Nightclub Shooting
- NBC News quoted unnamed law enforcement officials as saying Mateen called 911 moments before the attack to pledge allegiance to Abu Bakr al-Baghdadi, the leader of the Islamic State. Sources also told NBC News that, while at the scene of the attack, Mateen referenced the Tsarnaev brothers, who carried out the Boston Marathon bombings in 2013. President Barack Obama said the FBI is investigating the incident as an act of terrorism.
-Ron Hopper, the FBI agent overseeing the bureau's Tampa field division, said Mateen was questioned twice in 2013 for comments he made at work about possible contacts with terrorists, and again in 2014 for possible ties to an American suicide bomber. Hopper said the contact was "minimal" and agents determined he was "not a threat at that time." Despite his encounters with the FBI, Mateen legally purchased two of the weapons used in the attack in Florida in the past week, authorities said.
-NBC News also spoke with Mateen's father, Mir Seddique, who said his son got angry after he saw two men kissing in Miami a couple of months ago. "We are saying we are apologizing for the whole incident," Seddique said. "We weren't aware of any action he is taking. We are in shock like the whole country." He added, "This had nothing to do with religion."
Related: President Obama Says Florida Nightclub Shooting is an 'Act of Terrorism'
-Mateen had been licensed as a private security officer in Florida, according to the Associated Press, and records indicated that he held a firearms license in the state since at least 2011. It was set to expire in September 2017.
-Mateen's ex-wife told the Washington Post that he was abusive and mentally unstable. "He was not a stable person," she said, speaking to the paper on the condition of anonymity. "He beat me. He would just come home and start beating me up because the laundry wasn't finished or something like that." The couple married in 2009 but divorced in 2011. She said he worked as a guard at a facility for juvenile delinquents.
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