Christ, I know what happened, I visited the place before the quest and Killed everyone. Now there are only 3. Damn Beth screwing with exploration, I will only visit places during quests and seaching for shouts.
Yes, this is one of the more notorious bugs in the game, as it will hit you if you clear out Cragslane Cave before accepting the Skooma Den quest. Happened on my second character (and my first, though I didn't get far enough on that one to notice).
Compelled me to eventually start a new character; irony being that on my third character Blood on the Ice finally bugged out. Guess the game has something against property monopolies : /
Simple questions deserve long-winded answers that no one will bother to read.
RogerioFM posted... I will only visit places during quests and seaching for shouts.
Yeah, never go anywhere unless specifically told to go there. Also, make sure not to actually pick up anything that looks like it may be special. Unless you were told to do so. As doing so may break future quests.