The images captured outside Loveland’s Winona Elementary School would frighten any parent. Medical professionals surround children hooked up to oxygen tanks outside the school, while other students are led to buses, staring wide-eyed at the anxious-seeming adults in their midst. The photos were taken Tuesday after a noxious gas spurred complaints of nausea and dizziness at the school, resulting in an evacuation (slideshow via the Coloradoan). The symptoms sent 47 children and five adults to area hospitals, although all of them were treated and released by late afternoon (Reporter-Herald).

Firefighters and an Xcel Energy crew spent hours conducting tests with state-of-the-art equipment, but for now, the cause is still a mystery (7News). Officials’ hypotheses include the possibility that fumes somehow found their way into the school’s ventilation system, but left without concrete answers, some parents are concerned: “I’m wondering if I should have my daughter checked out myself,” says one. Fire and school officials tested the building early this morning, and classes have resumed today (Reporter-Herald).