ROBERT SIEGEL, HOST:

Authorities are still trying to piece together how a man in a Las Vegas hotel suite was able to shoot at thousands of people at an outdoor concert earlier this month. Questions have been raised about how the Mandalay Bay Resort and Casino responded when the gunman shot at a hotel security guard. The Clark County sheriff tried to put those questions to rest at a news conference today, and NPR's Leila Fadel joins us now to talk about it.

Leila, it seems like law enforcement has revised the timeline of when the attacker shot at the guard. What's the latest?

LEILA FADEL, BYLINE: Yeah. So this is the third version of when the security guard was shot. First we were led to believe that he was shot after the gunman fired into a crowd of concertgoers. Then on Monday, we were told he was shot six minutes before the mass shooting, which led to a lot of questions about whether or not the hotel alerted the police quickly. And if they didn't, then why didn't they?

And so now the Clark County sheriff, Joe Lombardo, in what I would describe as a pretty tense press conference - he wouldn't even take any questions - clarified the timeline again. And he says now that the guard got to the floor six minutes before the shooting, but he didn't actually get shot at some 200 times until pretty close to when the shooter shot out the window of the hotel. And here's Lombardo responding to some of the public criticism over that.

(SOUNDBITE OF PRESS CONFERENCE)

JOE LOMBARDO: Nobody is attempting to hide anything - reference to this investigation. The dynamics and the size of this investigation requires us to go through voluminous amounts of information in order to draw an accurate picture. My intent is to give you information as I know it, unverified, to calm the public, not to establish a legal case.

SIEGEL: Wow. You can hear the frustration, if not some anger, in the sheriff's voice there. Why is he so defensive?

FADEL: Well, it's that six-minute gap. Remember; before this press conference, the guard was said to have been shot at 9:59 p.m., six minutes before the shooter started shooting into the concert grounds. And that led to a lot of questions and even conspiracy theories out there that maybe the police and the hotel were in cahoots to deceive the public.

Now, there have been discrepancies in what we've been told, but what Lombardo says is he's, quote, "offended" about the questioning of his public releases, and he says these discrepancies come from trying to get information that he finds out quickly out to the public and be as transparent as possible. But because the investigation's still open, sometimes things change, and they might change again.

And now, he didn't dispute a statement from the MGM Resorts that said their guard was shot within 40 seconds of the time the gunman started shooting last Sunday outside - out the window and into the concert grounds.

Now, also remember; this sheriff has been dealing with what is the largest mass shooting in the country's modern history. He has injured officers. One of his officers was killed. And he's been dealing with the investigation in partnership with the FBI and also holding pretty regular briefings with the press. And so today, that stress, that tension was really apparent, and you can feel how much pressure he's under.

SIEGEL: You mentioned that there are police officers who were wounded. Can you talk more about that?

FADEL: Right. Lombardo brought up a couple of his wounded officers. And this was really a moment that the sheriff got pretty emotional. His eyes turned red, and he paused for quite a while to choke back tears. Here he's talking about one of his officers, Brady Cook. And Brady Cook had four gunshot wounds to - in his body when the sheriff visited him yesterday.

(SOUNDBITE OF PRESS CONFERENCE)

LOMBARDO: Brady sustained a substantial wound to his shoulder, through his bicep, into his chest and out his back. And the reason why I bring this one up - he asked me if he could go back to work today.

FADEL: Now, the sheriff says that Brady Cook is an officer who responded when those cars got to the location. The shooter started shooting at the police directly, and that might have stopped him from shooting at more people in the crowd.

SIEGEL: NPR's Leila Fadel in Los Vegas, thanks.

FADEL: Thank you. Transcript provided by NPR, Copyright NPR.

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