A bull elk was killed by a vehicle in Osage County 10 or so years ago. They did a search of all known captive animal ranches in the area and never found one that had lost an animal.I saw that same one, surprised one was that far North.
No proof, but there was speculation that it followed the Arkansas river from Colorado. We had a black bear pass through once, and a mountain lion that was killed by one of our coal trains in Noble county years ago as well. It was collared. Young male from South Dakota.
The Arkansas river runs within a few miles of each incident.