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Investigators in Nevada are looking through the evidence they collected at the homes of Stephen Paddock, the man who attacked the Las Vegas Strip Sunday night. He killed himself before police stormed his hotel room. Investigators have yet to determine a motive for what has become the deadliest mass shooting in modern American history, but they are hoping Paddock's computer hard drives will give some clues. They also hope to talk to his girlfriend, who has been out of the country. From Mesquite, Nev., NPR's Howard Berkes reports.
HOWARD BERKES, BYLINE: One thing is absolutely certain about 64-year-old Stephen Paddock. He loved guns and had his own private arsenal. This is what investigators found at his home in Mesquite according to Clark County Sheriff Joe Lombardo.
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JOE LOMBARDO: We retrieved in excess of 18 additional firearms, some explosives and several thousand rounds of ammo.
BERKES: And there were even more weapons and explosives in Paddock's hotel room and car in Las Vegas. But the size of the gun arsenal alone is not necessarily alarming, says Chris Michel, who met and spoke with Patrick three times earlier this year at Michel's Dixie GunWorx shop in St. George, Utah, nearby.
CHRIS MICHEL: It doesn't tell me anything because I have customers that have literally thousands of guns. Now, most of those are collectors, to an extent. I have customers that have hundreds of guns, and they're either using them for sporting purposes or collecting. No, that is not abnormal for me to see that from a lot of different customers.
BERKES: And there was nothing in his three gun shop encounters with Paddock that seemed extraordinary or troubling. He passed a background check when he made his one purchase, a shotgun in February. Other gun shop owners say the same thing when Paddock bought guns from them. And Michel says he passed a kind of smell test that helps...
MICHEL: Find out if there's any red flags that we feel immediately. If you get, you know, somebody that's sketchy that walks through our door, you know, we have code words between us. We let everybody in the shop know. And everybody goes on - not high alert, but we are alert to the person. And we start looking for any more red flags. All the employees, you know, that remember him coming through the doors - nothing got sent off.
BERKES: Michel adds was the kind of guy he would've invited home for a barbecue. Today, more about Paddock's past dribbled out. A federal spokeswoman said he had been a letter carrier with the Postal Service, an IRS agent and government auditor. His brother says he invested in real estate in multiple states and was a big gambler. The Nevada Gaming Control Board said today it was checking its records for anything on Paddock. Sharon Judy was a neighbor in Florida for two years and didn't notice anything alarming.
SHARON JUDY: He was a very nice person. I mean, he wasn't quirky in any way. He - you know, we never talked politics or religions or anything, any of that kind of stuff, so I have no idea what his thoughts were on that. But he was very friendly. There just wasn't anything, you know, really different about him than anybody else.
BERKES: And so that's the mystery. What caused Stephen Paddock to snap, to act in a way no one who has spoken out so far would have predicted? Investigators are hoping to learn more from his girlfriend, 62-year-old Marilou Danley. Sheriff Lombardo said she was overseas when the shooting occurred. Police have said she's not considered a suspect or accomplice, but maybe she knows something about Paddock's mental state. Paddock's brother Eric told NPR today he doesn't think Danley may know much.
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ERIC PADDOCK: My belief is what's going to happen when they talk to Marilou is they're going to find out that she - he bubbled her from this completely. He removed her completely away.
BERKES: And perhaps set aside some money to take care of her. Clark County Sheriff Lombardo said today investigators expect to speak with Danley soon. Howard Berkes, NPR News, Mesquite, Nev. Transcript provided by NPR, Copyright NPR.