張勉
At some time shortly after this, the May 12 plan was finally leaked by accident to the military security forces, who reported it to Prime Minister Chang Myon and Defense Minister Hyeon Seok-ho. Chang Myon was dissuaded from commissioning an investigation by the intervention of Army Chief of Staff Chang Do-yong, who convinced him that the security report was unreliable. Pervasive unrealized rumours of the imminence of a military coup also contributed to Chang Myon's decision, and the report on the May 12 plan was dismissed as a false alarm. The coup organizers responded by aborting the May 12 plan and fixing a new, and final, date and time, 3am on May 16.