(CNN) -- Phillip and Nancy Garrido have started serving sentences in separate California prisons for their roles in the abduction and rape of Jaycee Dugard, the state's corrections department announced Thursday.
The married couple held Dugard captive for 18 years.
They pleaded guilty to charges of kidnapping and sexual assault in late April. This month a judge sentenced Phillip Garrido to 431 years to life in prison. Nancy Garrido was sentenced to 36 years to life in prison.
Authorities received Phillip Garrido on Thursday at California State Prison-Corcoran in Kings County. He will be housed in a protective unit for inmates "whose safety would be endangered by general population placement," the corrections department said in a news release.
Nancy Garrido began serving her sentence Wednesday at Central California Women's Facility in Chowchilla.
Dugard was abducted from the street in front of her home in South Lake Tahoe, California, in 1991. She was 11 years old at the time of her kidnapping. Authorities found her in 2009.
During those years, the Garridos held Dugard in a hidden compound on their home's grounds in Antioch, California. She bore two daughters, fathered by Phillip Garrido.
A statement from Dugard -- now 31 -- read by her mother at the sentencing hearing earlier this month called the Garridos "evil" and described her kidnapping by them as a "sexual perversion."