A white phosphorus leak occurred at the US-operated Osan Air Base (K-55) in Pyeongtaek, South Korea, on Tuesday, prompting evacuation warnings for residents near the base. South Korea's Security Ministry announced the leak, and local authorities issued an emergency alert about the possible release of the toxic substance.
The leak was detected at around 5 pm local time. Two munitions leaked an unidentified amount of white phosphorus, a chemical substance used for cleaning warheads, inside the K-55 munition depot, according to reports.
Police established a perimeter this distance from the base.
Police set up a perimeter 300-500 meters from the base, and the US military established a 1,000-foot (300-meter) safety cordon around the site due to what was described as a ground mishap. Evacuation warnings were issued, but reports on the duration of the advisory vary: some sources say it was lifted after 36 minutes, others estimate around half an hour, while a third source reports several hours.
No casualties or injuries were reported. South Korean firefighters and US forces conducted decontamination operations. The US military stated the leaked substance was about 80% diluted and posed low risk to public health and the environment, adding that the situation is under control.
We are handling this matter with the utmost care and expediency.
The US Army stated the incident was due to an accident. The investigation into the leak is ongoing. US Forces Korea did not provide further comment about the incident. There were no immediate reports of major disruptions or accidents beyond the base perimeter.