A man posted an image on social media of a family vandalizing a historic landmark in Oregon’s Tumalo Falls, sparking an investigation.

According to The Oregonian, Brett Nelson was hiking Tumalo Falls on Saturday when he saw a man and two teenagers carving into the railing that is located under the falls. He asked them to stop defacing the landmark, but they refused to listen. The man who was with Nelson while hiking, Lyle Sweeney, took the photo of the man and his son and daughter.

On Nelson’s Facebook account, he wrote “PROUD parent letting children carve names in tumalo falls hand railing.” The photo shows the boy smiling and the girl holding her fingers in a peace sign.

Social media users began sharing the image in hopes of identifying the people in the photo while the Forest Service also began looking into it. Kassidy Kern, a spokeswoman with the Deschutes National Forest, said, “Brett doing what he did really helps us out. For as spoiled as his experience felt in the moment, it certainly has catalyzed a movement of people who really value public lands.”

Vandalism is not uncommon at the Falls, but having photographic evidence is reportedly why they are able to investigate. Nelson only found out that the man had a rental car and was from California.

Glen Satchet, a spokesman for the U.S. Forest Service said vandalism, “costs the public money, it damages the long-term sustainability of our resources and our facilities, and it’s ugly.”

In Oregon, it is considered a misdemeanor to deface public property. Nelson said all he wants is for “wrongdoing to be admitted and for all of us to move on.”