White Phosphorus Leak at Osan Air Base Prompts Evacuations

South Korean authorities ordered the evacuation of residents in Pyeongtaek on July 28, 2026, after a white phosphorus leak was detected at the U.S. Osan Air Base. The leak occurred around 5:00 p.m. during a routine inspection when experts identified white phosphorus crystallization and residue inside a munitions crate.

The U.S. 51st Fighter Wing responded by establishing a 300-meter safety cordon and deploying an explosive ordnance disposal unit to contain the munitions. Local government officials in Pyeongtaek issued text message alerts urging nearby residents to move to safe locations. While one report indicated the evacuation lasted approximately 30 minutes, other accounts state the alert was lifted several hours later following the completion of decontamination work.

Decontamination efforts were carried out jointly by South Korean fire authorities and U.S. forces. Base officials reported no injuries or casualties, stating there was no risk to personnel on or off the installation. The base has since returned to normal operations.