Inmates held at a UK prison for sex offenders are released without being challenged over their crimes or the risk they pose to others, a new report says.

The concerns have been raised by the Independent Monitoring Board for HMP Littlehey, which is the largest sex offenders’ prison in Europe.

The board says a “significant” group of inmates were missing out on a rehabilitation programme because they were classed as being at low risk of re-offending.

It is calling on the Ministry of Justice to set national standards for sex offenders and older inmates to “end the postcode lottery of rehabilitation and resettlement initiatives”.

The board said it was “frustrated to report the woefully small amount of men who are able to access an intervention programme to help them reduce their risk,” adding: “Together with the lack of resource for specific resettlement services, the board is dissatisfied with the help these men receive to become better citizens on release.”

Pointing out the size of the prison and the fact is has an unusually high” number of older inmates with 48% aged 50 and over, it continues: “[The] expectation is that Littlehey would be a leader of both managing imprisonment for men convicted of sexual offences and for OAPs. Sadly, this is not the case.

“The majority of the population will be released without being challenged, or increasing their own understanding, about their sexual offence, the factors leading up to it or what they need to do to reduce their risk of serious harm.”

The board also reiterated calls to the government to ensure the prison was not overcrowded, adding: “Housing two prisoners in cells designed for one person is not decent treatment and should not be accepted as standard practice.”

Ongoing maintenance problems with plumbing and unreliable laundry services were also raised in the report.

IMBs are made up of volunteers appointed by justice ministers to scrutinise prison conditions.

HMP Littlehey is a category C prison in Perry, Cambridgeshire, described as the largest prison in Europe for sex offenders, after it was re-categorised in 2014.

It holds over 1,000 inmates and 98% were convicted of a sexual offence.

Celebrity publicist Max Clifford – who denied his crimes up to his death in 2017 – was serving an eight-year sentence for indecent assault at Littlehey before he collapsed.