GRAND FORKS (AP) - University of North Dakota officials say human remains found on campus last fall appear to be from a commercially prepared specimen.

The mostly intact skeleton was found in October as work crews were excavating a site for a new steam line.

Mary Sens, who chairs UND's pathology department, said it was not uncommon many years ago for students to have their own specimens, and the remains likely are those of a specimen that a student buried before leaving UND.

The remains appear to be those of a middle-age woman of African descent, and may go back to the 1930s or 1940s, Sens said.

"Portions of the skull that were there clearly had evidence that there had been some injections with colored dye. Some cuts were made as if you were to demonstrate something in anatomy," Sens said.

"Up to 10 years ago, you could buy bones on eBay," she said. "Our best guess as to what happened is, this was likely a student specimen and when the student left the university, he or she buried it at that spot."

The UND medical school eventually will bury the bones.