LOS ANGELES • The Yellowstone National Park has warned tourists against entering the hot springs in the park as a report emerged that a man had died after falling into one.

Mr Colin Scott, 23, had gone to the park in Wyoming with his sister to "hot pot", or soak, in the thermal pools.

He slipped and fell into a hot spring as his sister was filming him on her mobile phone, according to a report on the incident obtained from park officials by local news channel KULR under a freedom-of-information request.

Mr Scott's body was dissolved in the boiling acidic waters.

The report said the incident happened on June 7 after Mr Scott and his sister, Ms Sable Scott, went into a dangerous area with boiling acidic waters that was clearly marked off-limits.

Yellowstone deputy chief ranger Lorant Veress warned that straying into the park beyond the official paths and signs was dangerous as much of the park's wilderness remains as untouched as possible.

"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," Mr Veress told KULR.

"They were specifically moving in that area for a place that they could potentially get into and soak. I think they call it hot potting."

Ms Scott told the authorities that her brother had reached down to check the temperature of the hot spring when he slipped and fell in.

Rescuers found his body inside the pool but were unable to retrieve it because of a lightning storm, according to the report.

The next day, the report said, rescuers could not find his remains. One of the few pieces of evidence recovered was the victim's flip-flops.

"In a very short order, there was a significant amount of dissolving," Mr Veress said.

Yellowstone covers 8,983 sq km and is one of the most-visited parks in the United States. According to park historian Lee Whittlesey, 22 people, including seven children, have died in the park's thermal pools - where temperatures can reach 121 deg C - since 1870.

Until this year, the most recent thermal fatality occurred in 2000 when a 20-year-old park employee dived into a hot spring that she had mistaken for a stream.

AGENCE FRANCE-PRESSE, WASHINGTON POST