ANTIOCH, Calif. Armed with rakes, shovels and chain saws, about 20 officers on Sunday combed the backyard of a couple charged with kidnapping and raping Jaycee Lee Dugard and used cadaver dogs to search an adjoining property where neighbors say one of the suspects once served as a caretaker.

Sheriffs deputies and prosecutors from two counties and officers from two city police departments were using the dogs, shovels and other tools to inspect the neighboring yard, which sits behind an off-white house with a chain link fence.

We do consider it a crime scene, said Jimmy Lee, a spokesman for the Contra Costa County Sheriffs Department.

Lee would not elaborate on what kind of evidence investigators were seeking or the nature of the possible crimes.