Orlando, Florida (CNN)An American-born man who'd pledged allegiance to ISIS gunned down 49 people early Sunday at a gay nightclub in Orlando, the deadliest mass shooting in the United States and the nation's worst terror attack since 9/11, authorities said.
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* The gunman, Omar Mateen, 29, of Fort Pierce, Florida, was interviewed by the FBI in 2013 and 2014 but was not found to be a threat, the FBI said.