HMP Wandsworth had the “worst year in memory” for inhumane conditions, the Independent Monitoring Board (IMB) has found.

Some 1,200 inmates were described as sharing “squalid, dirty and cramped” living conditions, in “crumbling” cells built for single occupancy in 1851.

Violence has risen on the “chaotic” wings, while staff were often unable to confirm prisoners’ whereabouts, nearly a year since the alleged escape of prisoner Daniel Khalife.

The Ministry of Justice (MoJ), which previously announced extra staff and £100m of funding for the prison, said it had “inherited a justice system in crisis”.

The “dangerously-overcrowded and vermin-infested” Victorian prison, was originally built for fewer than 1,000 prisoners.

But its population has increased to 1,513 in the last 12 months, the latest report states, despite an urgent population reduction being recommended last year to improve conditions.

There were 10 deaths in custody in the last reported year up to June, compared to four the year before.

Overall rates of violence, including serious assaults were on the rise. There were nearly 1,000 assaults on prisoners and staff, up from around 350 in 2017.

Most prisoners were unemployed and spent more than 22 hours a day locked up.

Staffing levels were just 50% of what they should be, with 50% of prison officers having less than a year’s experience, said the report.

Staff absences consistently led to failures in providing access to healthcare services, while a new multi-million pound healthcare centre remained unused, more than two years after its scheduled opening date in 2021.

The rate of self-harm was found to be high and rising, and around 40% of emergency cell bells were not answered within five minutes.

More than half the prisoners surveyed said it was easy to get illegal drugs and the smell of cannabis was ubiquitous.

Only 41% of prisoners said that staff treated them with respect, significantly lower than in comparable prisons.

Problems at the prison were due to a number of factors, the report suggested.

These included decaying infrastructure, staffing issues and insufficient or unhelpful management and lack of financial support from His Majesty’s Prison and Probation Service (HMPPS).

The chief inspector of prisons, Charlie Taylor, wrote to the Secretary of State on 8 May to invoke an “urgent notification process” following the unannounced inspection.

IMB chair, Matthew Andrews, said: “For HMP Wandsworth and the men whose treatment we monitor, this year has been as bad as any in our memory and, by many measures, worse.

“The recently released report was highly critical but said little that surprised us.

“Many of the same issues had been raised in previous IMB annual reports and ignored by the Ministry of Justice.”

An MoJ spokesperson said: “The new government inherited a justice system in crisis and has been forced to take action and get a grip of the situation across the prison estate, so we can lock up dangerous offenders, protect the public and make prisons safer for hard-working staff.”

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