Lives are at risk at the 'fundamentally unsafe' Nottingham prison, according to a watchdog.
Peter Clarke, the chief inspector of prisons, has written to justice secretary David Gauke about his concerns over the safety of inmates and staff there - and ordered him to take action within 28 days.
It is thought eight Nottingham HMP prisoners have taken their own lives in the past two years.
Inspections between 2016 and 2018 have found an increase in the number of inmates self-harming and high levels of drugs, violence and assaults.
The body of Newbold man Marc Maltby, 23, was found in Nottingham prison last October.
His mother described him as a 'a loving, bubbly, wonderful person who touched many hearts' and spoke of her grief at his death.
Marc was the prison's fifth inmate to die within a month and the second from Derbyshire.
Andrew Brown, 42, who lived in a cave in Baslow, died in hospital last September - five days after he was found hanging in his single cell at HMP Nottingham.
In his letter to Mr Gauke, Mr Clarke wrote: "It appears that the problems at Nottingham are intractable and that staff there are unable to improve safety despite the fact that this failing increases the vulnerability both of those who are held in the prison and of those who work there.
"Inspection findings at HMP Nottingham tell a story of dramatic decline since 2010.
"The principal reason I have decided to issue an urgent notification... is because for the third time in a row Her Majesty’s Inspectorate of Prisonshas found the prison to be fundamentally unsafe."
Mr Clarke told Mr Gauke there would be 'further tragedies' at the jail unless safety measures were put in place.
HMP Nottingham is a male category B prison, which takes prisoners from Nottinghamshire and Derbyshire courts, and has a capacity of 1,060 inmates.