The King County Medical Examiner’s Office in Seattle is asking for the public’s help to find who donated three human skulls to a thrift store.

There is no information about who donated the skulls to a Goodwill in Bellevue, Washington, or how they came to be in the donor’s possession.

The KCME said two of the skulls of from adults and were clearly used in a medical clinic or teaching setting.

The third skull is very old and appears to be the fragile remains of a Native American child.

According to Washington state law, the Native American skull must be returned to its tribe of origin, but the medical examiner needs more information to identify the correct tribe.

The office is asking that the person who donated the skulls come forward, without penalty, to provide more details on the origin of the skull.

The skulls were donated in June to the Goodwill, later employees there realized the skulls were human remains and contacted the Medical Examiner’s Office and police.