 The informers kept their identities secret, denounced fellow prisoners often, and worked assiduously to root out and finger potentially troublesome prisoners.Because of this, a massive chilling effect was created among prisoners, who feared opening up to or trusting each other.These national and ethnic blocs, though, began the fight against the informers, systematically fishing out and killing them with a vigour and efficiency so great that the remaining, unidentified informers fled to the camp administration for protection.