A prison crew from the Oregon Department of Corrections discovered a human skull discarded inside a backpack near a major highway, authorities say.
The skull had “no identifiable features” and is thought to belong to a woman in her late 30s or 40s, state police said in a statement.
The remains have been taken to the Oregon State Medical Examiner’s Office who are working to identify the victim.
Police have not released any other information.
Interstate 5 is a major thoroughfare that stretches from Mexico to Canada through California, Oregon and Washington state.
In 2018, a human skull was found by highway workers a few miles away in Douglas County near an off-ramp on Interstate 5.
More than a year later, it was identified as belonging to 44-year-old Oregon man Scott Evenson, who went missing in 2016, according to Oregon Live.
Evenson’s disappearance was never reported to police, but he had been listed as missing on a Facebook group, according to CBS News.