The plane, believed to be a twin-engine Beechcraft, went down in the Alaska Range south of Cantwell, the National Transportation Safety Board told the Anchorage Daily News.
The wreckage was found about noon after a state road maintenance worker spotted the crash site fire.
Clint Johnson of the NTSB said the plane went down in the vicinity of Summit Airport, but it was unclear whether it had taken off there, was on approach to land or just happened to be nearby.
The victims' names had not been released.
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