TRUCKEE (CBS/AP) — Federal investigators are trying to determine the cause of a small plane crash that killed a pilot near the Sierra town of Truckee.

The Federal Aviation Administration says the pilot was flying alone when the twin-engine Cessna 421 crashed Thursday afternoon in the Tahoe National Forest about 15 miles northeast of Truckee.

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The pilot’s name wasn’t immediately released.

The plane was en route from Santa Clara to Reno, Nev., when it went off radar about 20 miles west of its destination.

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Witnesses reported seeing a fireball in the sky before the plane went down.

The FAA says the plane was registered to Reno-based Tri-Wings LLC.

The National Transportation Safety Board is leading an investigation into the crash.

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