Los Angeles County sheriff's detectives found a skull and other bones in a La Puente backyard Friday, where they and coroner's officials were looking for the remains of a person missing since 2009, officials said.
Authorities first descended on the home Thursday morning about 7 a.m., after developing information that a missing person might have been buried on the property.
On Friday shortly before noon, searchers found the human bones, said county coroner spokesman Ed Winter. It will take some time before they are identified, he said.
Much of the scene was shielded from news helicopters by a row of investigators and a canopy.
The missing person is not believed to have been a resident at the home in the 700 block of Elsberry Avenue, officials said.
The family that lives there is cooperating with the investigation.
A coroner's official said the excavation had been planned earlier in the week.
For breaking California news, follow @JosephSerna.