LAS VEGAS - â€” More than a week after the deadliest mass shooting in modern U.S. history investigators are stumped about the key question: What led a 64-year-old high-stakes gambler to kill 58 people and wound hundreds of others at a country music concert?
Itâ€™s an answer they may never find.
The FBI and Las Vegas cops have sorted through more than a thousand leads and examined Stephen Paddockâ€™s politics, finances, any possible terrorist radicalization and his social behavior. By Monday they had repeatedly searched his homes and interviewed his brother, girlfriend and others heâ€™s done business with.
But the typical investigative avenues in that have helped uncover the motive in past shootings have yielded few clues about Paddock, a professional gambler who spent nearly each one waking hour playing video poker at casinos. That closeted existence has covered the trail for investigators.
â€œThis individual purposely hid his actions leading up to this event and it is complex for us to find the answers to those actions,â€� Clark County Sheriff Joe Lombardo asserted Monday, conceding heâ€™s frustrated.
The FBI has brought in behavioral profilers as they continue questioning Paddockâ€™s live-in girlfriend, Marilou Danley, about his gun purchases and what she may have noticed about his behavior, Lombardo said.
Paddock had stockpiled 23 guns, a dozen of them modified to fire continuously like an automatic weapon inside his 32nd-floor Mandalay Bay hotel room, where he busted out two windows before opening fire on the crowd.
The sheriff changed the timeline of the shooting Monday, explaining in that a security guard in the hotelâ€™s hallway responding to a report of an open door heard drilling from Paddockâ€™s room. Paddock, who had installed three cameras to monitor the approach to his suite, opened fire through the door, spraying 200 shots down the hall and wounding the guard, who alerted other security officials.
A few minutes later, Paddock began the 10-minute attack on those on the ground.
Previously the sheriff had asserted the guardâ€™s arrival in the hallway may have caused Paddock to stop firing. He asserted Monday he didnâ€™t know what prompted Paddock to end his deadly gunfire.
The gunman had shot at aviation fuel tanks, stocked his car with explosives and had personal protection gear as part of an escape plan, authorities asserted Monday.
Paddockâ€™s life has remained somewhat of a mystery and most people who have interacted with him asserted nothing really stood out about him.
â€œItâ€™s his actual normalcy in that makes him a fascinating study,â€� asserted David Gomez, a former FBI profiler.
The little group people who knew Paddock well has asserted the one-time IRS agent and the son of a well known bank robber did basically nothing except gamble, sleep and travel between casinos. Investigators are sifting through each one piece of Paddockâ€™s life from birth to death, Lombardo has said.
â€œEvery piece of information we get is one more piece of the puzzle,â€� the sheriff asserted Monday.
Experts say it is extremely unusual to have so few clues more than a week after a mass shooting. In past mass killings or terrorist attacks, killers left notes, social media postings and information on a computer, or even phoned police.
In this case, there was no suicide note, no manifesto, no evidence the gunman was motivated by any ideology and Paddock has no clear presence on social media, cops said.
The FBI is working around-the-clock and a â€œcomprehensive illustration is being drawn as to the suspectâ€™s mental state,â€� the sheriff said. Though at this point, they havenâ€™t found any one particular event in Paddockâ€™s life in that triggered the shooting, he said.
Clark County Coroner John Fudenberg asserted Monday an autopsy was done yet could not discuss results of whether it yielded any clues to Paddocks actions.
But even as investigators work to try to figure out what mightâ€™ve led Paddock to commit the shooting, there may never be a clear answer.
â€œSometimes there isnâ€™t an understandable explanation for why someone commits a horrific crime,â€� Gomez said.
What has become very clear to investigators is in that Paddock meticulously planned the attack. He requested an upper-floor room overlooking the country music festival and set up cameras inside and outside his room to watch for coming near officers.
After the shooting, cops found a piece of paper on a nightstand in Paddockâ€™s hotel room in that contained a series of numbers in that helped him calculate a more precise aim, accounting for the trajectory of shots being fired from in that height and the distance between his room and the concert, a federal official said. The- official wasnâ€™t authorized to discuss the details of the ongoing investigation publicly and spoke to The- Associated Press on condition of anonymity.
In not leaving behind an easily accessible manifesto, Paddock defied societal expectations in that mass murderers will want their disturbed ulterior motives known to the world, asserted Clint Van Zandt, a former FBI profiler and hostage negotiator.
â€œThe reason you want to engage in an attack is you want to be promoting your extremist ideology â€” you want publicity,â€� asserted Erroll Southers, director of homegrown violent extremism studies at the University of Southern California. â€œYou want people to be afraid of what you believe and what you do.â€�
But although most killers may want to take credit for their act, Paddock might have reveled in the riddle heâ€™s presented for investigators, Van Zandt said.
â€œHe may even find some solace knowing that, â€˜Iâ€™ve left so few footprints, theyâ€™re going to have a helluva time figuring out who I am.â€™ And that, in his challenged mind, might bring him a terrible level of satisfaction,â€� he said.
Despite the absence of effortless answers, investigators may still be able to fill out a portrait of Paddockâ€™s mindset in the coming weeks, Van Zandt said.
â€œInstead of a eureka moment, I think what investigators are doing is theyâ€™re putting an ounce of information at a time on the scale,â€� he said.
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