The Alameda Department of Public Works notified authorities around 9:30 a.m. that a crew had unearthed the remains while conducting maintenance in the 3000 block of Washington Street, police said.
The crew spotted the remains in mud after removing concrete in the area, police said.
Police said this afternoon they do not believe the remains came from Indian burial or sacred sites, but that the Alameda County coroner's bureau will determine that.
The coroner's bureau and Alameda Police Department are investigating the find.
