An inmate at Warkworth Institution died on Sunday.
Correctional Service of Canada Assistant Warden Anne Marie Joyce said 37-year-old Trevor Darroch died while in custody.
He had been serving a two year and 10 day sentence for dangerous operation of a motor vehicle, driving while disqualified and possession for the purpose of trafficking since February last year.
Next of kin were notified as well as police and the coroner.
