SEOUL, Oct 19 (Reuters) - A North Korean soldier defected to South Korea by crossing the heavily fortified demilitarized zone on Sunday, Yonhap News said, citing the Joint Chiefs of Staff. (Reporting by Hyunjoo Jin; Editing by Christian Schmollinger) (The article has been published through a syndicated feed. Except for the headline, the content has been published verbatim. Liability lies with original publisher.)