Autopsy Finds No Abnormalities in Las Vegas Shooter's Brain

Clark County Sheriff Joe Lombardo said Tuesday that Las Vegas shooter Stephen Paddock's brain showed no abnormalities in the autopsy. In the 10 days since the deadliest mass shooting in U.S. history, investigators still don't know Paddock's motive and Lombardo said we may never know the whole story.

In a Tuesday interview with The Las Vegas Review Journal, Lombardo said doctors started their autopsy on the 64-year-old Paddock. As of Tuesday, his brain showed no abnormalities, he said. However, the results of the toxicology tests have not been released.

Lombardo also said Tuesday that Paddock's girlfriend, Marilou Danley, told investigators that she was not concerned about his mental health.

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However, the Review-Journal reported on October 4 that Nevada Prescription Monitoring Program records show Paddock was prescribed diazepam tablets in June. Diazepam is an anti-anxiety medication, but can also be used to treat muscle spasms.

The shooting happened late October 1, during the Route 91 Harvest country music festival. Paddock fired from his room on the 32nd floor of the Mandalay Bay hotel and casino, across from the concert venue, killing 58 people and injuring nearly 500 others.

On Monday, Las Vegas police released more information on the shooting, clarifying the timing. According to the Review-Journal, police confirmed Paddock shot Mandalay Bay hotel security guard Jesus Campos six minutes before he opened fire on the crows at the festival. Lombardo also said Monday that Paddock checked into the hotel on September 25, three days earlier than previously thought.

In his Tuesday interview, Lombardo said investigators have learned new information every day since the shooting, but they are still not close to figuring out what motivated it. Investigators have yet to uncover a single possible event in his past that may have triggered it.

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“We may never know,” Lombardo told the Review-Journal Tuesday. “All those things that you would expect to find, we have not found.”

In his update on the investigation, Lombardo said Paddock spent the first three days at Mandalay Bay in a different hotel room, which he didn't have to pay for. He then moved over to the corner suite where he fired his weapons from. Investigators are not sure why the hotel provided the other room for free.

Police found Paddock dead in his hotel room when they entered.

Lombardo plans to give another update on the investigation Friday, but added that Danley and Paddock's brother Eric have not been cleared of wrongdoing. On Monday though he did confirm that there was not a second shooter.