Workers at an Arizona Goodwill location made a macabre discovery while rummaging through a donation box, a human skull. No, it wasn’t a plastic Halloween decoration.

An employee called law enforcement to report the bizarre discovery. A photo released by the Goodyear Police Department shows the skull with an artificial eye in the right socket.

Authorities took the skull to a medical examiner to determine if it could possibly be connected to a missing person case. The medical examiner concluded that the skull is not likely connected to any missing person case.

“It appears to be historic, ancient, and does not have any forensic value at all, and what that means is that no crime is attached to this skull,” Goodyear Police Department’s public information officer Lisa Berry stated.

“I’ve never heard of anything donated like this, especially here. I come to this Goodwill all the time and I’ve never heard of anything that crazy being donated,” Shopper Sydney Steele told CBS affiliate KPHO-TV.

After this spooky incident, shoppers may think twice before purchasing what they think are Halloween decorations from a thrift store.