  Let $G$ be a locally compact abelian (LCA) group. We denote by $G_{op}$, the
intersection of all open pure subgroups of $G$, which we call the $OP$ subgroup
of $G$. In this paper, we prove that the $OP$ subgroup of a torsion-free LCA
group $G$ is a non-zero pure subgroup of $G$.
