Investigators on Thursday said that two cadaver dogs showed interest in the same area in the yard, but said it doesn't necessarily mean anything specifically relating to the case is in that spot.
Crews will use special ground-penetrating radar equipment Friday to detect what might be in that area. An archaeologist might also join in on the search. Crews will also remove and dig under at least two randomly-poured slabs of concrete on the Garrido property Friday then resume the search Monday.
Investigators are also looking for clues in two other cases of missing girls.
Hayward officers were at the property seeking information related to the case of Michaela Garecht, abducted in 1998 at age 9 outside of a Hayward grocery store. Dublin investigators are there looking for ties to Ilene Misheloff, who was 13 when she disappeared in 1989.
The Garridos are charged with 29 counts in the kidnapping of Jaycee Lee Dugard in 1991. Phillip, a convicted sex offender, is being held on $30 million bail and Nancy is being held without bail.
Both defendants are due back in court in late October.