DAVID GREENE, HOST:
And I'm David Greene in Orlando, Fla., where we are reporting on the aftermath of the tragic mass killing at Pulse, a local gay nightclub, that left 50 people dead, including the lone gunman, Omar Mateen. At a candlelight vigil last night in downtown Orlando to remember the victims, we met Jonah Morgan (ph). Jonah's partner, sitting on the grass nearby, had lost a co-worker at the nightclub.
JONAH MORGAN: It's not just an attack on the LGBT community. It's not an attack just on one certain group. It's attack on humanity itself. I mean, these people - I mean, I have to wonder if they even have a heart. Is there anyone that they love? Is there anyone that they're close to? Is there anything behind just the exterior that goes in and shoots up an entire nightclub full of innocent people?
RENEE MONTAGNE, HOST:
And that again is Jonah Morgan in Orlando. One of our many colleagues covering this is NPR justice correspondent Carrie Johnson. And she joins us now in the studio. Carrie, good morning.
CARRIE JOHNSON, BYLINE: Good morning, Renee.
MONTAGNE: And what is the latest on the investigation into this attack?
JOHNSON: The FBI, in concert with local authorities, is following more than a hundred leads. They're reviewing the attacker's phone and seeking information from his relatives, including his wife. Renee, they're trying to understand whether he actually went to Pulse or other gay nightclubs and whether that was in an effort to case the joint before the attack or for some other purpose.
And his employer says he passed background checks, so does the gun shop owner that legally sold him at least two weapons in the last week or 10 days. So there are a lot of questions about his background and how he was able to avoid detection.
MONTAGNE: Might - also the FBI is saying that it is, I'm quoting, "highly confident the gunman was self-radicalized." Tell us about the clues that they're pointing to.
JOHNSON: They're not sharing all the information they have with us now because the investigation's ongoing. But it does appear clear from law enforcement sources that Omar Mateen was consuming a lot of virulent propaganda online - radical propaganda. And he mentioned, of course, in the call from the nightclub to 911 around 2:30 in the morning on Sunday that he had pledged allegiance to the Islamic State and its leader.
He also mentioned, according to law enforcement, the Tsarnaev brothers - the men who bombed the Boston Marathon - calling them his homeboys. So his grasp of recent radicals in the news was quite striking to investigators.
MONTAGNE: So quite a mix of layers or elements to - to his situation, whatever it turns out to be. But you were at the FBI director's press conference yesterday. And they had, as we know, interviewed Mateen.
JOHNSON: Yeah. They'd interviewed him twice in 2013 after his co-workers reported he made extremist statements and once again in 2014 after a man who attended his mosque went to Syria to become a suicide bomber. The FBI closed both those inquiries with no charges.
MONTAGNE: Carrie, thanks.
JOHNSON: You're welcome. Transcript provided by NPR, Copyright NPR.
