(SAN DIEGO) -- The man convicted of killing 17-year-old Chelsea King, whose body was found in a San Diego Park and 14-year-old Amber DuBois in Pala, California says he is an animal and expects to either kill himself or be taken out by other inmates as he serves his life sentence.
John Gardner, 31, tells CBS' 48 Hours Mystery for Saturday's show he knows that if he were free he would kill again.
"I am the type that needs to be locked up forever. I'm an animal."
Gardner is serving a life sentence after a plea bargain spared him the death sentence.
Gardner admitted he strangled Chelsea King and stabbed Amber DuBois and admitted attacking a female jogger in the same San Diego park just days before King was found there. The jogger escaped.
Gardner tells 48 Hours he hopes to be killed in prison. "Eventually someone will come and get to me...that will be a release for me."
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