The autopsy results for Las Vegas shooter Stephen Paddock have been released, but they don’t bring police any closer to discovering a motive for the 64-year-old’s attack, which killed 58 people and injured more than 500 others. According to the Las Vegas Review-Journal, the gunman had anti-anxiety medication in his system, but an examination of his brain done at Stanford University found no major abnormalities.

“It seems that based on the autopsy reports there were no physical excuses for what Steve did. We may never understand why Steve did this,” his younger brother Eric said, the Review-Journal reports. The autopsy also confirmed that Paddock died from a self-inflicted gunshot to the head.

las vegas shooting - getty

Concertgoers run for cover as bullets rain down around them.

On Oct. 1, 2017, Paddock carried out the deadliest mass shooting by a lone gunman in US history, opening fire on a crowd of concertgoers at the Route 91 Harvest music festival on the Las Vegas Strip from his suite on the 32nd floor of the Mandalay Bay hotel. Police found 23 weapons in his room, most of which were military-style rifles. They also found an additional 19 weapons in his home, as well as material to make explosives and 1,600 rounds of ammunition in his car.

Just one day after the shooting, his brother expressed shock and disbelief over the one-time real estate investor’s actions. “We have no idea how this happened. It’s like an asteroid just fell on top of our family,” Eric said from his home in Orlando. “There is no reason we can imagine why Stephen would do something like this. All we can do is send our condolences to the people who died. Just no reason, no warning.”

At the time, country singer Jason Aldean — who was performing onstage when Paddock began shooting — urged fans to stop the hate. “Over the last 24 hrs I have gone through lots of emotions. Scared, Anger, Heartache, Compassion and many others. I truly don’t understand why a person would want to take the life of another,” he wrote on Instagram.

“I am so sorry for the hurt and pain everyone is feeling right now and there are no words I can say to take that pain away. Just know u all are in my heart and my prayers as we all go through this together. Time to come together and stop the hate!”

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