The prehistoric facial bones were found buried in 50 feet of mud and silt, and are believed to be 1.1 to 1.4 million years old, researchers said.

The research team at the Atapuerca archaeological sites in Burgos, Spain, has just broken its own record by discovering, for the third time, the oldest human in Western Europe.

Researchers in Spain have discovered mysterious fossilized facial fragments that belonged to an unknown early human species. The bones are the oldest human fossils discovered in Western Europe, according to a study published this week in the journal Nature.