An FBI agent who spent 18 years on the Jaycee Lee Dugard case says the Antioch couple charged in her 1991 abduction were never considered suspects.

Special Agent Chris Campion said the bureau exhausted thousands of leads about Dugard's whereabouts, sometimes with the help of confidential informants and court-ordered wiretaps.

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Yet Campion said in the interview posted on the FBI Web site Friday that Phillip and Nancy Garrido "just did not come up on the radar screen."

"We've gone through and checked our records and my memory is no, we didn't have any thing that remotely was close to these people," Campion said. "We can tell you several thousands of people that didn't kidnap Jaycee Lee Dugard."

The Garridos have pleaded not guilty to kidnapping Dugard and holding her captive in their backyard.

Cadaver dogs returned to the property Monday to search for possible links to other open cases.

The secrets of the Garrido home began to surface early last week when Garrido arrived for a meeting with his parole officer with his wife, Dugard, now 29. and the two girls. Authorities say he confessed to snatching Dugard in 1991.

Over the years, Campion said he made a point of calling Dugard's mother every year on Dugard's birthday. He was the one who called to give her the news that her daughter was alive and he was present last week when they were reunited.

"It was a very emotional scene — both of them were just overjoyed to be with each other again," he said. "There's going to be a period of adjustment, no doubt, but they're doing very well at this point. And the two daughters are probably as happy as Jaycee is to be part of this family as well."