UPDATE: The National Park Service says the bison calf was rejected by its herd and had to be euthanized. Read more here.

ORIGINAL STORY:

YELLOWSTONE NATIONAL PARK, Wyo. — We’ve heard a lot about tourists trying to touch wildlife at Yellowstone National Park but this story takes personal encounters with animals a bit further.

Karen Richardson of Victor, Idaho, was one of several parents chaperoning a group of fifth-graders on a field trip to Yellowstone this week.

Richardson says on Monday, as students were being taught at Lamar Buffalo Ranch, a father and son pulled up at the ranger station with a bison calf in their SUV.

“They were demanding to speak with a ranger,” Richardson tells EastIdahoNews.com. “They were seriously worried that the calf was freezing and dying.”

Rob Heusevelet, a father of a student, told the men to remove the bison from their car and warned they could be in trouble for having the animal.

“They didn’t care,” Heusevelet says. “They sincerely thought they were doing a service and helping that calf by trying to save it from the cold.”

RELATED: YELLOWSTONE VISITOR CAUGHT ON CAMERA PETTING BISON

Law enforcement rangers were called and the father-and-son tourists, who were from another country, were ticketed.

Heusevelet says the rangers followed the pair back to where they had picked up the bison, and the animal was released.

Yellowstone visitors are not allowed to approach wildlife and are to stay at least 25 yards away from large animals, according to the National Park Service website.

The school group returned from their trip Friday, and Richardson posted a photo of the bison on Facebook with the caption:

Dear tourists: the bison calf is not cold and it is not lost. PUT IT BACK!

EastIdahoNews.com has reached out to Yellowstone authorities and has yet to hear back, but there is no doubt the National Park Service would agree with that statement.

READ: DEPUTIES INVESTIGATING SHOOTING DEATH OF CALF (WARNING: GRAPHIC PHOTO)