More than 10 months after the deadliest mass shooting in modern U.S. history, police say they are closing their investigation without answering the key question: What drove a gunman to unleash a hail of gunfire that killed 58 people and wounded hundreds more?

But authorities say after hundreds of interviews and thousands of hours of investigative work, they are confident there is no evidence of a conspiracy or a second gunman.

Stephen Paddock was an "unremarkable man" who showed signs of a troubled mind leading up to the Oct. 1 shooting on the Las Vegas Strip, Clark County Sheriff Joe Lombardo said Friday. He also was a reclusive, high-stakes gambler who spent more than $1 million in the year leading up to the shooting.

"What we have been able to answer are the questions of who, what, when, where and how," Lombardo said. "What we have not been able to definitively answer is ... why Stephen Paddock committed this act."

Paddock, who fired across Las Vegas Boulevard from a room on the 32nd floor of the Mandalay Bay hotel into a concert crowd of 22,000 people, was the only gunman, the sheriff said.

Lombardo said that with the closure of the Las Vegas Metropolitan Police Department's 10-month investigation, no one else will be charged in connection with the deadliest mass shooting in modern U.S. history.

Earlier this year, federal prosecutors brought criminal charges against a man who they say sold illegal armor-piercing bullets that were found in Paddock's room. Douglas Haig has pleaded not guilty and maintains he sold tracer ammunition, which illuminate a bullet's path.

Lombardo said that while authorities cannot answer Paddock's motive, they are trying to leave "no stone unturned." He said the FBI's Behavioral Analysis Unit is expected to release a psychological profile of the gunman later this year.

Lombardo said interviews with Paddock's doctor indicated he had a "troubled mind" but displayed no behavior leading up to the shooting that would have prompted someone to alert police.

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I THINK we JUST did this....

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I THINK we JUST did this....

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Dang, search failed me.  Shut 'er down boys.

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Dupe

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lol. Just move along, nothing to see here!

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Well that settles it.  Case closed.

Now you can show us all the information the LVPD collected since there is no conspiracy and Paddock acted alone.

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Dang, search failed me.  Shut 'er down boys.