Stephen Paddock, the 64-year-old perpetrator of the deadliest shooting in modern US history, may have considered other targets in Chicago, Las Vegas, and Boston before he ultimately carried out his attack in Las Vegas on Sunday night that left 58 people dead and more than 500 injured.
Authorities say Paddock booked rooms overlooking the Lollapalooza music festival in Chicago in August and the Life Is Beautiful concert in Las Vegas in September and also researched hotels near Boston's Fenway Park, the home of the Red Sox.
Paddock booked a room in The Blackstone Hotel across from Grant Park, where Lollapalooza was held, during the first week of the festival, and he rented a room at The Ogden, a luxury high-rise with a line of sight to the Life Is Beautiful concert grounds near the Las Vegas Strip.
Though it is unclear what his intentions with those actions, he ultimately chose to mount an attack from the Mandalay Bay Resort and Casino across the street from the Route 91 Harvest country music festival held last weekend. A high-stakes gambler and regular at the Mandalay Bay, Paddock checked into his 32nd-floor suite on September 28, three days before his meticulously planned attack.
Investigators have found 47 firearms that belonged to Paddock, a dozen of which were converted to mimic fully automatic weapons. After finding materials for explosives and 1,600 rounds of ammunition in his car, investigators are also looking into whether Paddock planned another attack.
Paddock, who officials believe had an escape planned, fatally shot himself as a SWAT team descended on his hotel room.
"Stephen Paddock is a man who spent decades acquiring weapons and ammo and living a secret life, much of which will never be fully understood," Clark County Sheriff Joseph Lombardo said at a news briefing on Wednesday night.
"We have a lot of work to do," FBI Deputy Director Andrew McCabe told reporters on Wednesday.
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