The Biebs was in Barcelona, driving to perform Tuesday night, when a guy ran up to the car and stuck his hand in the window to touch him. Bieber responded with a quick jab to the face.
The guy ended up a bloody mess as he and his friends reacted in shock.
Anyway, I don't blame arrogant celebrities like Justin Bieber, I blame their obsessed fans helping to make them even more famous, poor chap!
Watch the humiliating video below