 The shooter was at a distance of 200 to 300 yards away in an elevated position. He was on a rooftop adjacent to the venue, and those same law enforcement sources are telling ABC News he fired as many as eight rounds from an AR-15-style rifle. FBI Special Agent in Charge Kevin Rochek. We do not currently have an identified motive, although our investigators are working tirelessly to attempt to identify what that motive was.