South Korean authorities on Tuesday briefly ordered civilians to evacuate following a reported white phosphorus leak at the U.S. Osan Air Base, located near the capital, Seoul.
Officials in Pyeongtaek, the city adjacent to the base, urged nearby residents to move to a safe location and avoid skin exposure after the incident was detected around 5 p.m. local time. The evacuation order was lifted several hours later after decontamination efforts were completed, according to text messages issued by the city. No major disruptions or accidents were immediately reported.
Police reportedly established a perimeter of approximately 1,000 to 1,700 feet (300 to 500 meters) from the base, diverting pedestrians and rerouting traffic.
In a statement, the U.S. 51st Fighter Wing at Osan Air Base did not confirm a white phosphorus leak but stated that a 1,000-foot (300-meter) safety cordon was established around the base. This measure was taken "due to a ground mishap and out of an abundance of caution" to ensure the safety of the base and the local population. The wing also clarified that reports of a general evacuation of the air base were inaccurate.
"We are handling this matter with the utmost care and expediency," the statement read. "The safety and well-being of our service members, their families, and our Pyeongtaek neighbors remain our absolute highest priority."
U.S. Forces Korea provided no further comment on the incident. White phosphorus is a chemical compound used in incendiary munitions and smoke shells. When ignited, it can burn at high temperatures, potentially causing severe burns and igniting structures.