Google Translate of heise.de storyA group of people calling themselves "die Partei" (the party) managed to infiltrate the AfD (Alternative for Germany Party, German right-wing, nationalist party, think of a cross between UKIP and National Front) on Facebook and over the course of 12 months managed to escalate their position to become administrators of the AfD's Facebook pages, then promptly changed the from private to public and started changing the rules and posting satirical apology videos and information that runs contrary to what AfD stands for.
They didn't hack anything, they just used social engineering to climb up the ranks of the AfD's Facebook presence, until they managed to gain control of the pages on the social network. Hats off!