Police in eastern North Carolina are investigating after a “historical” human bone was found at a dog park.

The Rocky Mount Police Department said someone reported finding the bone Wednesday at the Best Friend’s Dog Park and a “preliminary investigation” revealed it was human, WSOC reports.

“According to an anthropologist, due to the extensive weathering of the human bone, it is historical, which means it is estimated to be close to 100 years old,” police said in the release. “The Rocky Mount Police Department will continue to investigate the situation.”