LOUISVILLE, (WDRB) -- A massive search is taking place after a 16-year-old Cincinnati girl mysteriously vanished while taking part in a service project in a park in Wyoming.

WXIX Fox 19 is reporting that Fauna Jackson never returned from a bathroom break while hiking at Grand Teton National Park, according to a statement from the park. She was with a group of 20 Groundwork USA volunteers.

"Jackson, a sophomore at Clark Montessori High School, left Cincinnati nine days ago to work on a service project at the park, according to Robin Corather, executive director of Groundwork Cincinnati," Fox 19 reported. "She was supposed to return home Friday with three other volunteers from the local Groundwork chapter."

Federal agents joined a team of 100 people searching for Jackson, utilizing specialized dog teams, helicopters and infrared imaging.

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