More bones found at kidnap house

Police Lieutenant Christine Orrey said it was too early to tell if the bones were human after dozens of investigators spent a second day digging at the home of Garrido and a neighbouring property in Antioch, east of San Francisco.

"We have located what appear to be bones on both properties," Orrey said, adding that the bones had been sent to a laboratory for analysis.

"Finding them is the first step in the process."

Kidnap, rape, imprisonment charges

Investigators are seeking evidence linking Phillip and Nancy Garrido, who face 29 counts of kidnapping, rape and false imprisonment in the Jaycee Lee Dugard case, to two girls who disappeared in the 1980s.

The Garridos are accused of kidnapping 11-year-old Dugard and keeping her in a makeshift compound in their backyard for 18 years until her discovery in late August.

Phillip Garrido is accused of fathering two children with Dugard.

A week ago, a bone fragment found on the adjacent property was said by police to be "probably human", but it was not clear how old it was.

Authorities have stressed that bones from Native Americans are often found in northern California.