Woodhill Prison in Milton Keynes recorded one of the highest numbers of self-inflicted deaths in England and Wales last year, according to figures released by The Howard League for Penal Reform.
With four self-inflicted deaths during 2013, only Wormwood Scrubs Prison in London – which has a significantly larger population – recorded more suicides, with five.
In total there were five deaths at Woodhill in 2013, including one from natural causes.
There was just one death from self-inflicted injuries at Woodhill in each of the previous two years.
The Howard League for Penal Reform is calling for urgent action after figures for last year showed a sharp rise in the number of suspected murders and self-inflicted deaths behind bars across the country.
It says the number of suicides at prisons in England in Wales in 2013 was the highest for six years.
In total, 199 deaths were reported, 70 of which were self-inflicted.
More than 100 prisoners died of natural causes and a further 22 deaths are yet to be classified by prison authorities.
The statistics are based on notifications from the Ministry of Justice, which records deaths in custody.
Frances Crook, Chief Executive of the Howard League for Penal Reform, said: “Each death in custody is a tragedy and almost all of them are preventable.
“The responsibility for an increase in the number of people who take their own lives in prison lies squarely with those who advocate putting behind bars more and more people who do not need to be there.
“This is the consequence of a policy that squanders a scarce resource, meaning that these institutions cannot keep people safe.”
In October the Citizen reported that Woodhill Prison was at risk of becoming a dangerous place for staff and prisoners alike, due to budget cuts.
That was the verdict of the prison’s annual report, published by the Independent Monitoring Board, which gave a behind-the-scenes glimpse of life at the city jail.
The report said: “The Board is increasingly concerned that the year-on-year increases in cuts and services and facilities may lead to a potential loss of control, making the prison unsafe for both staff and prisoners.”