And so far, investigators in Las Vegas, Nevada are having difficulty finding a motive for the worst mass shooting in the U.S. modern history.
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The ABC7 I-Team's Dan Noyes has been investigating Stephen Craig Paddock's possible ties to the Bay Area. By many accounts, the 64-year-old was a high stakes gambler, making millions on real estate.
He married twice and was living with a girlfriend in a retirement community 80 miles northeast of Las Vegas.
It is still unclear why he opened fire on concert-goers, but ABC News is reporting Paddock had 19 guns in his Mandalay Bay Hotel room, including some that were high powered and capable of penetrating police armor.
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One law enforcement source said Paddock also had mounted a camera in the room, apparently to record himself.
Online records list addresses for Paddock in Nevada, Texas and Southern California. There is only one Bay Area address that comes back to Stephen Paddock and that's in Hayes Valley dating back to March 2008. No one was home at that location when Noyes knocked at the door.
A next door neighbor expressed shock about the possibility that the man responsible for such devastation in Nevada may have lived there, even if it was years ago. "It's eerie and it feels strange to know that someone like that lives next door, or lived next door, you never know who you live next to," Leyby Cali-Garcia said.
Other people who lived in the area for a long time tried, but couldn't remember Paddock. They did know the man also listed at that address who may have been Paddock's roommate.
One thing doesn't make sense - this address is low-income housing and by many reports, Paddock was a wealthy man.
According to court records, Paddock filed a slip and fall case in 2012 against Cosmopolitan Hotel in Las Vega, but he lost and the case was dismissed.
Paddock's father was on the FBI's "Ten Most Wanted List" after breaking out of a federal prison in Texas and robbing a San Francisco bank in 1969.
The wanted poster listed Benjamin Paddock with several aliases including, "Big Daddy", "Chromedome", "Old Baldy".
And the FBI poster described him as "psychopathic" with "suicidal tendencies", warning he should be "considered armed and very dangerous."
Nearly half a century later, the son of that accused bank robber has become the worst mass murderer in U.S. modern history.
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