ST. PAUL, Minn. (AP) - St. Paul police say a father and son have discovered part of a human skull as they hiked through Battle Creek Regional Park.

The discovery happened Friday morning. The age and identity of the skull remain under investigation.

The hikers led police to the unpaved trail along the cliffside where they discovered the top portion of the skull.

A police spokesman tells reporters that police searched the area but did not find any other bones.

The skull has been turned over to the Ramsey County medical examiner's office.