South Korea’s safety ministry says a “leak” of white phosphorus occurs inside the U.S. Osan Air Base in South Korea on Tuesday, prompting an evacuation advisory for residents near the base. Multiple outlets report that the alert is issued in the nearby area around Pyeongtaek, where U.S. Forces Korea is based. Local police and fire authorities receive calls from the U.S. military at about 5:07 p.m., according to one report. The regional city government issues public notification to move people to a safe location to reduce the risk of skin exposure. Authorities state that no casualties are reported. One report says the suspected leak comes from two munitions, though the exact quantity released is not confirmed. The U.S. military reportedly tells local officials that the material is roughly 80 percent dilute, which officials describe as posing a low risk. White phosphorus is described across coverage as extremely toxic and capable of causing severe burns on contact. Officials continue to assess the situation as the advisory remains in place for nearby residents.