An inmate was found dead at the Mid North Coast Correctional Centre on Sunday.
A Corrective Services NSW spokeswoman said police are investigating the incident.
"Corrective Services NSW extends its sympathies to the family and friends of a 24-year-old-man who died at the Mid North Coast Correctional Centre on Sunday," the spokeswoman said.
"Corrective Services NSW and NSW Police are investigating the incident."
All deaths in custody are subject to a coronial inquest.
The spokeswoman said Corrective Services are in full cooperation with NSW Police.
"We support the coronial investigation and are assisting fully the NSW Police and the Coroner," the spokeswoman said.
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