Both Lorde and Chance the Rapper were the headlining acts.
64-year-old Paddock may have scoped out the three-day Life is handsome festival held September 22-24 from multiple rooms at The Ogden, a 21-story tower overlooking festival grounds in downtown Las Vegas.
The "Life is Beautiful" festival "was held in Las Vegas just over a week ago" and "had a line-up including Blink-182, Chance the Rapper and Lorde".
The Daily Beast says the source is not "directly involved in the investigation but has been briefed on its progress".
The sheriff was asked at a news conference if it's believed that Paddock was scouting other locations in Las Vegas, and he said only "what's possibly been presented with Life is attractive". While attendance figures for this year's festival are unconfirmed, the 2016 festival drew over 137,000 music fans to the grounds over three days, a far greater number than the 22,000 reported to have attended the Route 91 Harvest Music Festival this year.More news: Google Home Mini: Price, release date and features
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While it's still an ongoing investigation, the public affairs officer for Fais Foley Warren and owner of the Ogden, was not able to confirm or deny whether Paddock rented out a condo unit in their building.
The spokesperson for The Ogden told ABC News declined to answer questions and told ABC News to talk to Las Vegas police.
With new information being revealed daily, we continue to keep the victims and the families of those affected in our prayers and thoughts. I have to tell you, I had an eerie feeling that night.
"Life is lovely is founded in the beliefs of community and our collective love for each other and the arts as well as making the world a more handsome and loving place", Weninger added. "We will lean on each other to move forward and to create a world in which love is the only option".