A view of a hot spring at the Norris Geyser Basin at Yellowstone National Park on May 12, 2016.
Yellowstone, the first National Park in the US and widely held to be the first national park in the world, is known for its wildlife and its many geothermal features.  / AFP / MLADEN ANTONOV        (Photo credit should read MLADEN ANTONOV/AFP/Getty Images)
MLADEN ANTONOV/AFP/Getty Images/FILE
A view of a hot spring at the Norris Geyser Basin at Yellowstone National Park on May 12, 2016. Yellowstone, the first National Park in the US and widely held to be the first national park in the world, is known for its wildlife and its many geothermal features. / AFP / MLADEN ANTONOV (Photo credit should read MLADEN ANTONOV/AFP/Getty Images)
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Story highlights

His body has not been recovered

Norris Geyser Basin is the hottest thermal area in the park

(CNN) —  

A man visiting Yellowstone National Park was killed after he stepped off a designated boardwalk, slipped and fell into a hot spring.

Colin Nathaniel Scott, 23, of Portland, Oregon, was with his sister when he fell in near the Noris Basin Geyser on Tuesday, officials said.

His body has not yet been recovered. Authorities were proceeding with caution because of the heat around the springs.

“This tragic event must remind all of us to follow the regulations and stay on boardwalks when visiting Yellowstone’s geyser basins,” said park Superintendent Dan Wenk.

The park website describes the site as the hottest thermal area in Yellowstone. It says that the superheated water of geysers can reach the boiling point while circulating deep in the Earth and as high as 400 degrees Fahrenheit, or 205 degrees Celsius, within the geyser plumbing system as it pushes upward.

Over the weekend, a 13-year-old boy burned his ankle and foot when he fell into a hot pool in Yellowstone’s Upper Geyser Basin. His father slipped while carrying him, the Billings Gazette reported.

CNN’s Steve Visser contributed to this report