In all missions I played till now, the game always told me I killed at least 1 or 2 people, which I definitely didn't. The only explanation I found for this, is that the game also counts indirect kills (once, a guard I knocked out at the beginning of the mission was just eaten by rats when I came back later). While I can accept the design decision, that such kills are also counted, I wonder why there is no kill counter that can be viewed thoughout the mission. This would extremely lower frustation when finishing a mission after 3 hours of playing and just finding that a single kill was counted somehow.