Multiple incidents involving Chinese mainland and Taiwanese nationals violating national security near various ROK-US military facilities in South Korea have occurred in succession, putting the military on high alert. Related individuals have used tourism or study as a cover, but in fact have conducted long-term surveillance near military facilities, used professional equipment to collect communication information, and even attempted to approach personnel inside the facilities, with their methods of crime continuing to escalate.
Earlier this month, the Southern Gyeonggi Provincial Police detained two Chinese individuals suspected of engaging in acts benefiting the enemy near ROK-US military facilities. Among them, a Chinese man in his 60s, identified as 'A,' is suspected of intercepting communications between fighter jets and control towers at a hotel near Gunsan Airport in North Jeolla Province, where ROK-US air force combat assets are stationed, in April. Upon investigation, police discovered A is a retired military officer who came to South Korea several times since January this year using a tourist visa, specifically during joint ROK-US air force drills.
Another Chinese national in his 40s, 'B', was also arrested recently. B is suspected, from November 2021 to May this year, of operating a military goods store as a cover near the main gate of the USFK Pyeongtaek Base (K-6), in order to collect classified information. B allegedly bribed a Korean employee working at the base to obtain materials related to the ROK-US “Ulchi Freedom Shield” (UFS) joint exercises, high-level personnel documents, and also observed and filmed the movement of weapons inside the base. B is also a retired military veteran. Police are conducting digital forensics on both suspects' electronic devices to investigate whether any collected information may have been leaked to relevant Chinese authorities, among other details.
It is not the first time that Chinese nationals have been caught perpetrating hostile acts near South Korean military bases. In May this year, two Chinese high school students were sentenced to prison for unauthorized filming near key ROK-US military installations and international airports, as well as intercepting air traffic control communications. This marked the first time foreigners have been convicted and sentenced under South Korea’s “General Act Benefiting the Enemy” provision in the Criminal Code. From the second half of 2024 through March last year, the two filmed four military facilities—Suwon Air Base, Pyeongtaek Osan Air Base (K-55), USFK Pyeongtaek Base (K-6), Cheongju Air Base—as well as fighter jets and air traffic facilities at three international airports.
Additionally, last year, the ROK Defense Counterintelligence Command found a case in which a Chinese national bribed active-duty soldiers to steal military secrets. The person was suspected of infiltrating open chat rooms for active-duty soldiers, then entering into one-on-one conversations with serving officers and noncommissioned officers, using money as bait to induce them to leak military information. This person was subsequently sentenced to five years in prison.
In May last year, two Taiwanese individuals received suspended sentences for unlawfully entering the flight show area at Osan Air Base (K-55) in Pyeongtaek and filming fighter jets. In August of the same year, two Chinese tourists were discovered using a drone to film the area around the Jeju Naval Base.
According to data obtained by National Assembly National Defense Committee member Yoo Yong-won from the National Police Agency, from 2020 to August 2025, a total of 14 foreign nationals were referred for investigation (or not prosecuted) for violating the “Military Bases and Military Facilities Protection Act.” Of these, 7 cases occurred last year, with 4 involving Chinese mainland citizens and 3 involving Taiwanese nationals.
The ROK military has also expressed deep concern about the continuing frequency of foreign nationals violating national security, pledging to strengthen cooperation with relevant agencies and respond actively. Experts believe that such espionage activities could pose a fatal threat to the security of the Korean peninsula. Ryu Ji-hoon, a research fellow at the Korea Institute for Defense Analyses (KIDA), stated that repeated information protection breaches not only raise suspicions from the US side but might also erode trust in ROK-US intelligence cooperation. He suggested that prevention efforts should not be limited to individuals of specific nationalities, but rather focus on behavioral patterns of intelligence-gathering at military and high-tech facilities, further enhancing detection and protection capabilities.