Jaycee Dugard had been missing since she was abducted near her home in South Lake Tahoe, east of San Francisco, on June 10, 1991, by two people in a gray sedan.

"It's a pretty spectacular story just to find someone like that. Someone we assumed was dead," said Bill Clark, the chief assistant district attorney for El Dorado County, an area east of Sacramento that stretches into the Sierra Nevada and to South Lake Tahoe.

Dugard's alleged kidnapper, Phillip Craig Garrido, 58, a registered sex offender in California who served time in prison for rape and kidnapping, and Nancy Garrido, 54, were in custody after being arrested on Wednesday, police said.

Dugard was healthy, El Dorado Undersheriff Fred Kollar said, but "living in a backyard the last 18 years must take its toll," he added.

"None of the children had ever been to school, none had been to a doctor, they were kept in complete isolation in this compound, if you will, at the house," Kollar said.

Suspicions were first raised after Garrido tried to enter the University of California at Berkeley campus to pass out leaflets with his two daughters.

His interaction with the two female minors, aged 11 and 15, raised suspicion and a police officer looked into his background.

The next day, during a visit with his parole officer, Garrido brought his wife, the two minors and a female named Allissa -- who later proved to be Dugard -- whom the officer had never seen before.

The district attorney's office said it would file charges by Friday.

Dugard was walking to a bus stop near her home when the gray sedan pulled up next to her and she was yanked inside.

Carl Probyn, the girl's stepfather, told television that "we both cried for about 10 minutes" after he and her mother were alerted by authorities that she had been found alive.