The process begins in a reception center like Green Haven where Heuermann will undergo medical and security assessments.
"Rex Heuermann is currently undergoing admission processing at Green Haven Correctional Facility, one of the Department's designated intake facilities," the New York State Department of Corrections and Community Supervision said in a statement.
Heuermann will not remain there permanently, as he will be assigned a state prison based on an evaluation of criminal history, security risk, medical, mental health, and program needs.
Heuermann was sentenced to consecutive life sentences after he pleaded guilty to killing seven women and admitted to killing an eighth.
He spent three years in a Suffolk County jail where the sheriff told ABC News he read macabre novels and corresponded with at least one fellow serial killer.
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