A father and son hiking through St. Paul's Battle Creek Regional Park Friday morning found the top portion of a human skull, police said Monday.

The age and identity of the skull remain under investigation, and it's unclear whether it's linked to any suspicious deaths.

"They were just walking and it was right along the dirt path," said police spokesman Sgt. Mike Ernster. "Battle Creek Park is heavily used, but I don't know if all those paths are used equally to others. Some of those paths are … rugged."

The skull was found about 10:45 a.m. Friday, according to a police report. Ernster said the hikers led police to the unpaved trail along the cliffside where they discovered the skull, which was not concealed by brush or leaves.

Police searched the area but did not find any other bones or items of interest, Ernster said. It was turned over to the Ramsey County medical examiner's office, which confirmed it was human.

People often dump garbage, including tires and couches, at the county-operated park, but Ernster said he can't recall police ever discovering crime evidence there.

Although the skull's origins remain under investigation, it's not unusual to find ancient American Indian bones in the metropolitan area.

Minnesota is home to an estimated 12,000 known burial mounds, the final resting places built by Indians from about 500 B.C. through 1500 A.D.

Battle Creek Regional Park is adjacent to Indian Mounds Park, which is home to six burial mounds.

John Siqveland, a Ramsey County spokesman, said there are no known burial sites inside Battle Creek, and that there is no knowledge of remains being found there in the past.

Homeless camps have been discovered in the park, but none have been spotted recently, he said.

An anthropologist will examine the skull for further evaluation.

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