JACKSON, Wyo. (AP) — A lightning strike at an outdoors educator course in the Bridger-Teton National Forest in Wyoming killed one student and injured another, officials said Thursday.

The group with the National Outdoor Leadership School was just days into their trip and had set up camp near Enos Lake, south of Yellowstone National Park, when a thunderstorm moved into the area Tuesday evening.

John D. Murphy, 22, of Boston, died of cardiac arrest because of the lightning strike, Teton County Coroner Brent Blue said Thursday. Blue did not know if the lightning struck Murphy directly or passed through something else to him.

The injured student was flown to an Idaho hospital for treatment and released Wednesday, Shana Tarter, the school’s associate director for wilderness medicine, told the Jackson Hole News & Guide.

Nine other students, three instructors and two search and rescue members stayed the night in the back country after the lightning strike, school officials said.

Two people at the course who didn’t think they were capable of doing the 12-mile (19-kilometer) hike from the lake to the trailhead were flown out by helicopter Wednesday morning and the rest of the group hiked out, said Matt Hansen with Teton County Search and Rescue.

National Outdoor Leadership School President Terry Watson in a statement called the lightning strike a “a very sad day” for the school, its students and their families.

“We extend our deepest condolences to the family of our student who passed away on this course and are focused on supporting their family through its difficult process,” she said.

The nonprofit global wilderness school based in Lander, Wyoming, teaches students to become outdoors educators. More than 330,000 students have graduated and there have been 13 deaths at school events during its 57-year history, the school said.

A 20-year-old man training with the school in 2011 fell down a 300-foot (91 meter) ravine into a river while backpacking in India during rainy conditions.

His mother filed a lawsuit against the school, but a Wyoming judge ruled that the contract the man signed releasing the school from liability prevented his survivors from suing the school.

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