Investigators are trying to determine whether anyone else was in the Las Vegas gunman’s hotel room during the time he was registered there, multiple senior law enforcement officials briefed on the investigation told NBC News.
The investigators are puzzled by two discoveries: First, a charger was found that does not match any of the cellphones that belonged to the gunman, Stephen Paddock.
And second: Garage records show that during a period when Paddock’s car left the hotel garage, one of his key cards was used to get into his room.
There are several possible explanations for these anomalies, the investigators say, but they want to get to the bottom of it.
They are also examining his finances. IRS records show that Paddock was a successful gambler, earning at least $5 million in 2015. Some of that could be from other investments, but most of it was from gambling, officials say.
Paddock unleashed a barrage of bullets from the 32nd floor of the Mandalay Bay and Casino on Sunday night, killing at least 59 people and injuring about 500 others who were attending a country music festival below.
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His motive is still unclear. Senior law enforcement officials said Paddock, 64, had researched possible attack locations in Boston and Chicago, including the Lollapalooza festival in Chicago in August.