Lim Seong-geun
Overview
Lim Seong-geun (임성근) is a retired major general of the Republic of Korea Marine Corps. At the time of the death of Corporal Chae Su-geun (채수근) in July 2023, during search operations for missing persons amid torrential rains in Yecheon County, North Gyeongsang Province, he was commander of the 1st Marine Division. After the incident, as he became subject to investigations by military investigative authorities, police, and the Corruption Investigation Office for High-ranking Officials (CIO; 고위공직자범죄수사처), he became known as a central figure in controversies over command responsibility and the reporting system. Because several people share the same name (including a soccer player), context is needed to distinguish them.
Main Content
Military Career
Lim Seong-geun was commissioned as a Marine Corps officer and served in various command and staff positions; after promotion to major general, he assumed command of the 1st Marine Division. The 1st Division is one of the Marine Corps' main units and has repeatedly been deployed for search, rescue, and recovery support missions in disaster situations such as typhoons and heavy rains, as well as for large-scale field training. During the torrential rains in the summer of 2023, it also supported search missions for missing persons in the Yecheon area, and the division commander stood at the top of the command chain for that operation.
Death of Corporal Chae Su-geun
On July 19, 2023, Corporal Chae Su-geun of the Marine Corps, who was conducting a search mission for missing persons in Yecheon, North Gyeongsang Province, died in the line of duty after being swept away by rapid currents. Immediately after the accident, the Marine Corps Investigation Unit (then commanded by Colonel Park Jung-hoon) raised issues with safety measures and the command system for the search mission and sought to book commanders, including division commander Lim Seong-geun, on charges such as occupational negligence causing death, and to transfer the case to the police. However, controversy arose when the Ministry of National Defense requested that the transfer be postponed and retrieved the case records; afterward, allegations of intervention by political circles and the presidential office, along with the issue of the independence of military investigative authorities, expanded the case into a social issue.
Investigation and Controversy
The case became prolonged as the investigating body shifted among the military prosecution, police, and the CIO. Lim Seong-geun stated that he denied the charges, and controversy was raised several times over statements concerning the reporting and approval process at the time of the accident. Meanwhile, Colonel Park Jung-hoon (박정훈) was indicted on charges including insubordination for failing to follow orders from superiors and stood trial; in January 2025, he was acquitted in the first instance. The case is assessed as having shed light simultaneously on the military's internal culture of command responsibility, military investigative authority, and military human rights issues.
Command Responsibility and Institutional Reform Discussions
Apart from identifying the direct cause of the accident, the key issues included whether safety equipment and control procedures were sufficiently secured when deploying troops for a dangerous search mission, and whether reports were properly made when abnormal situations occurred. Interpretations differed among legal circles and inside and outside the military over how far to recognize commanders' criminal and disciplinary responsibility, and this led to growing calls to institutionally improve risk assessment and command reporting systems for disaster support operations.
Latest Developments
From 2024 through 2025, the CIO has investigated Lim Seong-geun and other related persons over allegations of external pressure in the death of Corporal Chae Su-geun and charges such as dereliction of duty and occupational negligence. Lim Seong-geun was summoned for questioning as a suspect, and whether he will be indicted and whether the prosecution can be sustained remain major issues. In addition, the National Assembly and civil society have continued to demand institutional improvements that clarify military investigative authority and the scope of responsibility of senior commanders, along with establishing the truth of the case. Because follow-up judgments may vary depending on the results of related trials and investigations, the matter is classified as an ongoing case as of 2025.
Related Topics
- [[Death of Corporal Chae Su-geun]]
- [[Park Jung-hoon]]
- [[Republic of Korea Marine Corps]]
- [[Corruption Investigation Office for High-ranking Officials]]
- [[Military human rights]]