Fury as Yellowstone tourists filmed dangerously close to scalding waters of world-famous hot spring

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Two tourists have been slammed online after being seen walking perilously close to the boiling waters of a world-famous hot spring. 

Footage shot by Tanya Saueressig, of Livingston, Montana, showed the moment inside Yellowstone National Park when two women began approaching the Grand Prismatic Spring around 7pm local time Sunday after veering off-track. 

The women nonchalantly walked on the spring's colorful microbial mats, which shine hues of yellow, orange and red thanks to the heat-loving bacteria around the edges of the pool.

Saueressig said she stopped in her tracks when she spotted the women near the 160-foot-deep spring, which has a center that reaches 188° F.

'Is that people?' Saueressig recalled thinking. 'That can't be people. Nobody's that dumb.'

The National Park Service has warned that even if the ground around Yellowstone may look solid, it can be 'just a thin crust with super-heated water below.'

Not only was the act extremely dangerous, but it was also illegal and could lead to repercussions for the two women, who are yet to be identified.

Traveling off boardwalks or designated trails is illegal at Yellowstone, according to the US Code of Federal Regulations.

Saueressig said she initially started getting scared when she sighted the two women within feet of the scalding waters.

They appeared to be walking from the Fairy Falls Trail, which goes along the western edge of Grand Prismatic, which is the third largest hot spring in the world.

'I thought they were going to fall in and get really, really hurt,' she said.

She was also concerned that people at the overlook would 'watch someone die that day,' as there was no one to help the two women.

But as Saueressig continued watching, she said that fear turned into a fury that caused her to 'literally [have] tears in my eyes.'

'You could tell they were just strolling along, taking their selfies, without a care in the world,' she said.

'They were totally oblivious to what was right under their feet,' Saueressig added. 'You're causing so much damage with every step you take, and you don't care.'

Though Saueressig wanted to report the incident to a Yellowstone ranger, she could not find any, which made her feel increasingly 'helpless' about what she was witnessing.

'You can help them or stop them because it's already happening,' she told the outlet. 'I didn't have cell reception, so I couldn't call anybody. There wasn't anybody I could run up to and notify. I didn't know what to do.'

Instead, she decided to film the video, hoping that it could lead to the women being found and held responsible.

As of Tuesday night, the two women have been identified. Yellowstone has not publicly commented on the incident.

Still, Saueressig insisted that she was concerned about more than the park, worrying that the two women could even die because of their irresponsible actions.

To date, more than 20 people have died from burns suffered entering or falling into Yellowstone's hot springs, according to the National Park Service.

Last June, a bison died at Grand Prismatic Spring while tourists watched, according to CBS News.

The beast would have stumbled into a deep section of the spring before being unable to get out.

'If they didn't die, they were leaving permanent scars on the microbial mats,' she said.

Saueressig lamented how the 'really nice experience' with a 'lovely' crowd had turned sour.

'They were causing so much damage with every step they took, and they literally didn't care at all,' she told the outlet.

Other Yellowstone visitors who have walked off the designated trails at Yellowstone have faced legal repercussions.

In April, In March, 50-year-old Eric Bedient, of Frisco, Texas, was sentenced to five days of incarceration for walking on 'several fragile and dangerous hydrothermal features' in the Mammoth Hot Springs area.

Then, US Attorney Darin Smith called Yellowstone's thermal areas 'among the most dangerous natural features in the world.'

He cautioned that sort of behavior could be fatal and that prosecuting these crimes could deter others from 'risking becoming thermal soup.'

The Daily Mail has reached out to Yellowstone National Park and the National Park Service for comment.