(Newser) – Plenty of Norwegians thought aliens had taken a fancy to their country back in the 1950s thanks to a slew of inexplicable UFO sightings. Inexplicable no more: It was the CIA, reports the BBC. Actually, it was the CIA itself that fessed up in this tweet, which reads in part, "Remember reports of unusual activity in the skies in the '50s? That was us." It then provides a government writeup about the sightings, which weren't caused by alien spaceships but by U2 spy planes being tested.