Photo: the National Intelligence Service.  Credit: Website of the National Intelligence Service.

According to MBC News, Won Se-hun 원세훈, then-chief of the National Intelligence Service 국가정보원, pushed South Korean embassies abroad to delay issuing new passports to Korean nationals - who tend to lean liberal, as they are often study abroad students - so as to limit their ability to vote.

The NIS whistle blower also claimed that he was tortured after objecting to the operation by being placed for several days in a small white room intended to cause sensory disorientation. Won is currently serving a prison sentence for a different domestic political interference.