An unknown hazardous material release sickened about 200 people in the U.S. state of New Mexico on Tuesday, state officials said. A mandatory evacuation was under way for two miles (about 3.2 kilometers) around an industrial park and border crossing at Santa Teresa, New Mexico, and the nearby airport was closed, according to KFOXtv.com. Emergency crews at the scene said about 200 people were being treated for exposure to an unknown substance, with symptoms of difficulty breathing, light-headedness, nausea and dizziness. No serious injuries have been reported, and no one has yet been transported to hospitals, according to several media reports. Emergency officials from Texas and New Mexico responded, and people in nearby homes and businesses were told to stay indoors. The evacuation remained in effect while air-quality testing was being done to determine what made the people sick, according to reports.