A U.S. Marine Corps drone operator assembles a small unmanned aircraft system during a bilateral combined-arms live-fire range in Gimpo, South Korea, March 18, 2026. (Robert Blanks/U.S. Marine Corps)
The South Korean military prepared to shoot down a U.S. Marine Corps drone near the inter-Korean border Thursday after mistaking it for an enemy threat, prompting an emergency notice for nearby civilians to seek shelter, according to media reports.
U.S. Forces Korea spokeswoman Choi Min-jung confirmed in an email Friday that the drone belongs to the U.S. military and that the incident happened during a training exercise by U.S. and South Korean marines.
Marine personnel are investigating the matter in coordination with their South Korean counterparts and appropriate local authorities, Choi said.
She did not immediately respond to a follow-up request for details about the circumstances surrounding the event.
South Korean forces spotted an unidentified aerial object south of the Military Demarcation Line on Thursday, mistook it for an enemy threat and prepared to shoot it down, the Chosun Daily reported Friday.
The South Korean army’s 1st Corps subsequently declared a “durumi,” a military air-defense alert issued when an unidentified aerial object is detected and assessed as a potential threat.
The South Korean military held its fire after determining the drone’s flight path and appearance differed from those typically associated with North Korean drones, the report said, citing unnamed military officials.
The U.S. military notified South Korean forces of the training in advance, but that information was not relayed from the operational level to higher command, the report added.
However, the South Korean military said the United States did not go through the proper approval process to fly drones near the Military Demarcation Line, South Korean broadcaster KBS reported Friday.
The Ministry of National Defense cannot share details of the incident because of operational security concerns, a ministry spokesman said in a text message to reporters Friday. The Joint Chiefs of Staff will visit 1st Corps on Friday to review the military’s response, the spokesman said.
Yonhap News Agency reported Thursday that an emergency alert from an unidentified sender was sent to several village leaders near the border, warning: “An unmanned drone has been detected in the Cheorwon area. People north of the Civilian Control Line should move to a nearby shelter or leave the control line. This is a real-world situation.”
The South Korean military is investigating to determine who sent the message, according to the report.
This was the second emergency notice sent to civilians involving U.S. forces in South Korea in a week.
On Tuesday, residents near Osan Air Base received an emergency mobile alert from Pyeongtaek city warning of a white phosphorus leak on the base, advising people in the affected area to evacuate and avoid skin exposure.
Osan, about 40 miles south of Seoul, is home to the U.S. 7th Air Force and the 51st Fighter Wing.
The wing confirmed that night that white phosphorus residue was discovered inside a munitions crate during a routine inspection.
The South Korean government is in talks with the U.S. military to gain access to the air base for a safety inspection, Yonhap reported Thursday, citing unnamed sources.
Seoul plans to conduct air quality monitoring near the leak site to ensure the area is safe for residents, according to the report.