FWIW, now the Swedish navy is saying "we´re still certain there was a foreign sub, just that one sighting was actually of something else".
@alien invasion through Siberia:
Evening in a remote Siberian taiga. A flying saucer quietly lands on a clearing.
Small, grey humanoid climbs out and heads towards a nearby logging camp, where loggers are sitting around a fire and having their evening drink.
Not wishing to upset them, he timidly steps into the light and says: "Hello, people!".
"Hello!", responds a chorus of voices, and a glass of vodka is immediately passed to the humanoid. Otherwise, nobody raises an eyebrow.
Humanoid respectfully finishes the vodka, decides the encounter is going well and continues: "My name is Sirius!". "Hello, Sirius!" responds a chorus of voices and the glass gets an immediate refill.
Humanoid, by now slightly surprised of being taken so in stride, decides to get some more attention. "People, I come to you from the stars, from another galaxy!".
Brief moment of silence. Then, a deep voice declares: "All right guys. No more vodka for Sirius tonight!".