SAN JOSE -- Authorities Thursday were investigating human bones found in the city, Sgt. Ronnie Lopez said.

Police responded at about 1:45 p.m. Wednesday to Bailey Avenue west of Santa Teresa Boulevard in response to a death investigation, Lopez said.

A person walking in the area discovered a partially unearthed skull and notified the Police Department, Lopez said.

Police were not able to determine the gender or age of the person based on a cursory search of the partially exposed remains, Lopez said. The size of the skull, however, appears to be that of an adult's.

He said it appears the body has been there for some time, due to the absence of body tissue.

He said police are coordinating efforts with the Santa Clara County medical examiner's office to conduct a cursory anthropologic assessment of the bones to eliminate the possible connection to any Native American burial sites.

Police are working to remove the remains to determine if foul play was involved, Lopez said.

More information will be released once the bones are unearthed. Lopez said it will be a slow and methodical process.