Former National Security Chief Questioned in THAAD Leak Investigation

On March 30, 2025, it was reported that the prosecution is investigating allegations that high-ranking officials from the Moon Jae-in administration leaked sensitive military operation details between South Korea and the United States to delay the formal deployment of the THAAD (Terminal High Altitude Area Defense) system. Former National Security Advisor Chung Eui-yong has been summoned for questioning as a suspect in this case.

According to sources, the Seoul Central District Prosecutors' Office's Public Investigation Division 3, led by Chief Kim Tae-hoon, is currently interrogating Chung in his capacity as a suspect. The investigation centers around Chung, former Deputy National Security Advisor Suh Joo-seok, former Minister of National Defense Jeong Kyeong-doo, and former Presidential Secretary for Civil Participation Lee Gi-heon. They are accused of intentionally prolonging the formal deployment of THAAD, which was temporarily stationed in Seongju County, by over a year through a 'general environmental impact assessment' process and delaying the formation of a committee for the assessment.

The core of the allegations suggests that they leaked classified information regarding U.S.-South Korea military operations related to missile replacements at the THAAD site to Chinese authorities and civic groups opposing the deployment. This investigation was prompted by a public interest audit requested by the Korea Defense Security Reserve Officers Association in July 2023. Following the audit, the Board of Audit and Inspection referred the case to the Supreme Prosecutors' Office in October of last year.

In January, the prosecution began a thorough investigation, conducting searches at Suh's residence and locations associated with protests against the THAAD deployment in the village of Soseong-ri, Seongju County.