A monument marked where historic oil lease auctions took place that brought wealth to the Osage Nation and changed the course of the tribe’s history in the early 20th century.

The original tree died in the 1980s from Dutch elm disease, according to the Oklahoma Historical Society. But a replacement tree was planted a decade ago to commemorate the old elm.

According to Osage News, the elm was initially believed to be damaged from storms that passed through the tribal headquarters. Officials told the newspaper they realized the act was likely intentional after discovering clean cuts and yellow paint remnants left behind.

Surveillance footage of the area is currently under review, and officials ask for any information on the crime to be reported to the Osage Nation police department.

You can make a report to Osage Nation authorities at 918-287-5510.