Peter Sutcliffe, the serial killer known as the Yorkshire Ripper, died in hospital on Friday, a Prison Service spokesman said.
The 74-year-old was convicted in 1981 of killing 13 women and trying to murder seven more between 1975 and 1980.
A Prison Service spokesman said: “HMP Frankland prisoner Peter Coonan (born Sutcliffe) died in hospital on 13 November. The Prisons and Probation Ombudsman has been informed.”
Sutcliffe had tested positive for Covid-19 and was suffering from underlying health conditions.
There was no confirmation of the cause of death which will be investigated by the coroner.