(NBC News) 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.

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