Investigators are looking into two key pieces of evidence that seem to suggest that Las Vegas shooter Stephen Paddock was not entirely alone in his Mandalay Bay hotel room.
Senior law enforcement officials told NBC News that they have made two discoveries in Paddock's 32nd-floor hotel room that they currently cannot explain.
The first is a cell phone charger that does not match any of the devices that belonged to the gunman.
The second is a hotel record showing that one of Paddock's key cards was used to access his room while his car was outside of the hotel's parking garage.
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Investigators told NBC News that while there are many possible explanations for these two puzzling finds, they are hoping to get to the bottom of things immediately.
A mysterious piece of paper was also found in the shooter's hotel room, where he opened fire on the Route 91 Harvest country music festival Sunday night, killing at least 59 concertgoers and injuring more than 500.
Although investigators have confirmed it is not a suicide note, there has still been much speculation about what may have been on the paper.
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