Because Aliens!

1947 - Seaman Harold Dahl claims to have seen six UFOs near Maury Island in Puget Sound, Washington.  The next morning, Dahl reported a man arrived at his home and invited him to breakfast at a nearby diner; Dahl accepted the invitation.  He described the man as wearing a black suit and driving a new 1947 Buick; Dahl assumed he was a military or government representative. Dahl claimed the man told him details of the UFO sighting while they ate, though Dahl had not related his account publicly.  The man also allegedly gave Dahl a non-specific warning, which Dahl took as a threat that his family might be harmed if he related details of the sighting.

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