It is shown that the correlations predicted by relativistic quantum field theory in locally normal states between projections in local von Neumann algebras A(V 1 ), A(V 2 ) associated with spacelike separated spacetime regions V 1 , V 2 have a (Reichenbachian) common cause located in the union of the backward light cones of V 1 and V 2 . Further comments on causality and independence in quantum field theory are made.