A man has dissolved in an acidic hot pool in Yellowstone National Park after falling in, according to reports.
Colin Nathaniel Scott of Portland, Oregon, and his sister had been hiking near the Norris Geyser on June 7 last year, Montana-based news organisation Kurl8 reported.
They strayed from the main path in order to find a hot pool to soak in - a prohibited activity in the park.
The official incident report quotes the sister as saying her brother was "reaching down to check the temperature of a hot spring when he slipped and fell into the pool".
Search and rescue rangers arrived and found the victim's body but a lightning storm delayed recovery efforts.
The next day they could not find the remains.
"In a very short order, there was a significant amount of dissolving," said Deputy Chief Ranger Lorant Veress.
"There's a closure in place to keep people from doing that for their own safety and also to protect the resources because they are very fragile. But, most importantly, for the safety of people because it's a very unforgiving environment."