JACKSON — An investigation report Yellowstone National Park officials released this week sheds no light on a key question surrounding the death of a man whose foot was found floating in a hot spring in mid-August.

How or why Il Hun Ro, 70, of Los Angeles, ended up in the Abyss Pool remains a mystery.

Three days after finding the foot, park officials issued a statement saying they suspected no foul play. The investigative report released Tuesday via a Freedom of Information Act request offers no evidence or explanation about how park officials reached that conclusion.

The 36-page report notes the family was contacted, and a family member provided a DNA sample to help identify remains. But the document doesn’t say much else about interactions with the family, including whether they were able to speak to Ro’s travel plans or state of mind. Law enforcement searched for but didn’t find evidence of a suicide note.

“NPS staff was in contact with family. There is no information as to why he might have fallen into the hot spring,” Yellowstone spokeswoman Linda Veress said Tuesday.”Yellowstone is a large park with thousands of visitors traveling through it each day,” Veress said. “No individuals have been identified who may have seen Mr. Ro the day he disappeared.”The park has not released a photo of Ro though officials found his driver’s license and other photos in his car.

Teton County Coroner Dr. Brent Blue helped the park identify Ro’s remains. He said officials haven’t determined a clear cause of death. The reason: Evidence is scant. Blue said officials assume Ro drowned, but that’s only an assumption. He said he has no other information to use to determine how he died.

“There’s no way we’re going to ever be able to determine that,” he said. “The only evidence we have is a foot. That didn’t give us a lot of information. We don’t know anything about the other circumstances.”

Blue also said his office was only involved with making a DNA match — not investigating the circumstances surrounding Ro’s death. The responsibility to do so fell on Yellowstone rangers and investigators.

A month or so before Yellowstone confirmed that Ro’s foot had been found in the pool, the Wyoming Department of Criminal Investigation said the man was likely deceased in a Yellowstone hot spring. Scott McWilliams, director of the state crime lab, said that, like Blue, DCI only helped identify the foot.

It was not involved in investigating Ro’s death, McWilliams said.

In the report, which contains narratives from the first two days of the investigation, park officials redacted personal information of the investigators involved and witnesses interviewed. To justify doing so, they cited provisions in the Freedom of Information Act that allow federal agencies to keep information private if releasing it would be an “unwarranted invasion of personal privacy.”

Park officials’ names were redacted. Also redacted was the language Ro used to write on notebooks and papers found in his car. Officials used Google Translate to scan his writings for signs of a suicide note but said they found none.

The investigation began Aug. 16, when a tour driver for Xanterra, a private concessionaire that runs the park’s lodges, told another person that a shoe was floating in Abyss Pool. That person tried to call a ranger station around 11:30 a.m. but got no answer. An hour later, the person who’d been told about the foot made contact with a park employee.

Shortly after, a supervisory interpretation ranger working at the West Thumb Geyser Basin heard about the shoe. The supervisor picked up a tool used to retrieve items from hot springs and headed for Abyss Pool.

“I found this odd because we have pulled two shoe soles out prior to today in this past week,” that unnamed ranger wrote in a statement provided to Yellowstone law enforcement on Aug. 16.

The ranger struggled to get the shoe out of the pool. Once successful, the ranger quickly dropped the shoe just outside the pool’s edge and closed the area.

“There appeared to be something in the shoe,” the ranger said.

The shoe also had no sole.

Law enforcement arrived soon after and took statements from the supervisor, the person who spoke with the Xanterra driver and another ranger working near Abyss Pool. They also attempted to find the drivers of three vehicles unaccounted for in the West Thumb parking lot after visitors left. One person was found quickly. Another claimed her car that evening. But the third car, a blue 2018 Kia Niro, remained.

Investigators determined the third car belonged to Ro and found his phone number.

“I left a message on the phone requesting that Ro call me back as soon as he could to confirm that he was safe,” an investigator wrote.

That call never came.

Meanwhile, rangers put on personal protective equipment and retrieved the shoe, placing it in a biohazard bag. It was size 8 1/2.

The foot and shoe were transferred to Dave Hodges of the Teton County Sheriff’s Office, a certified coroner. Investigators weren’t able to contact Ro’s family that day. His car was given a “Notice of Intent to Impound Abandoned Vehicle.” Investigators left the scene around 9 p.m.

Around 11 a.m. the following day, Jackson Hole Fire/EMS helped Yellowstone rangers search the area. Officials flew drones over Abyss Pool — and 200 feet in either direction — but found no additional remains in the pool, or other items surrounding the hot spring, one of Yellowstone’s deepest.

Geologists arrived an hour later to traverse the rim of Abyss Pool but found no “significant remains.”

“Fatty deposits were found floating to the surface over time, and geologists took samples of what appeared to be the fatty tissues dispersed in film on the water’s surface,” the report states.

Around 1:30 p.m., investigators searched Ro’s car.

They found a laptop, notepad, wallet, a photo of Ro and someone else at the Statue of Liberty, a notebook, photo album, Pacific Crest Trail notebook, Yellowstone park maps and a photo of Ro and someone else at a baseball game. Investigators called Xanterra Lodges and confirmed that Ro had checked into Canyon Lodges on July 30 and checked out the morning of July 31.

His foot was found two weeks later.

On Aug. 19, law enforcement asked a park ranger to assess “some papers with writing that could possibly be a suicide note.”

The report states that officials were in contact with someone that was willing to translate, but the translator’s name was redacted. The ranger was given instructions on how to translate and used Google Translate.

“I was unable to find anything consistent with a suicide note,” that ranger wrote.

They checked Ro’s vehicle again but found no other possible note. Another search on Aug. 22 turned up nothing other than a book of poems printed in another language. It also had handwritten notes in another language. The language was redacted. There is no other mention of the poems in the report.

As the investigation continued, the report states that investigators used what was found in the vehicle to contact Ro’s family.

One of his relatives agreed to provide a DNA sample to confirm a match with his remains. McWilliams, the director of the State Crime Lab, said he believed the person who provided an oral swab was Ro’s daughter. The State Crime Lab conducted the test, and it came back positive.

“Since every person is a 50-50 mixture of their mother and father, we did see that half the DNA in that sample matched the daughter,” McWilliams told the News&Guide Tuesday.

A ranger assigned as a family liaison returned all of Ro’s property to his next of kin. Imaging of his laptop was captured by the National Park Service’s Investigative Services Branch, but there was no further mention of that in the report.

The report also does not say how many times the park spoke with Ro’s family, or whether the family was asked if they had any clues as to what happened.

Coroner Blue said the report is all the information the public is likely to get.

"As far as we know, there were no other circumstances other than he was visiting the park,” Blue said.

This story was published on Jan. 4, 2023.