BERN, Switzerland, Oct. 23 (UPI) --
A Swiss FA-18 fighter jet crashed Wednesday in dense fog in the Swiss Alps, military officials said. It was unclear if there were any casualties.
Witnesses told 20min.ch they heard two jets flying overhead in foggy skies and shortly thereafter heard a boom and saw a "huge ball of fire" in the distance.
The crash near a road and railway tunnel interrupted rail service in the area, with passengers being taken by buses from the village of Alpnach to their destinations.
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