A new report has warned that within the UK’s first majority Muslim prison, non-Muslim inmates are being pressured to convert to an “Islamic protection racket” which forms the largest “power block” in the jail.

The number of Muslims in Whitemoor prison in Cambridgeshire is thought to be double what it was in 2008, and the highest proportion in any UK prison. Even then, prison staff were warning about radicalisation. It now appears the situation is deteriorating at a rapid pace.

“About half the prisoners on Whitemoor’s main wings are Muslim, profoundly affecting the social nature of the jail and disrupting established hierarchies,” the report from the Independent Monitoring Board – which makes judgements on prisoner welfare – reads.

It conluded: “Against this background we note that some prisoners and staff found the Muslim presence overwhelming. The social and religious fragmentation within Whitemoor potentially posed risks for discipline and hence safety.”

Nationally, the UK’s prison population is roughly 15 per cent. However, the report revealed that Whitemoor’s Islamic population has shot up from 40 per cent just one year earlier, and 28 per cent in 2008. Between the ages of 22 and 39, Muslims now represent 56 per cent of the population there.

“Not only were Muslims the largest religion, they were the largest power block, displacing the greater multiplicity of gangs that had previously existed,” the report said.

The report then highlights a section of a groundbreaking study into the phenomenon of the Islamisation in prisons, published in 2012 by Alison Liebling, which refers to Whitemoor:

“There were some intimidating ‘heavy players’ among the Muslim population who appeared to be orchestrating prison power dynamics rather than propagating or following the faith. “Many physically powerful players ‘re-establishing their outside identities’ as leader in the prison and used their (newly-acquired) faith status as a tool for establishing status.”

Inmates told Liebling and her researchers that they were often bullied into converting to Islam, and those who resisted were too scared to cook pork in communal kitchens in case it caused offence.

Some prisoners claimed that the jail functioned as a “recruiting ground” for extremism as younger inmates were “in awe” of convicted terrorists held there.

Mark Icke, vice-president of the Prison Governors Association, defended Whitemoor:

“We have a prison population which is bigger, serving longer sentences, more prone to violence, and increasingly driven by gang affiliations.

“Use of legal highs, which we cannot yet test for, has destabilised the system further,” he told the Daily Mail.

Last month experts from the Quilliam Foundation advised that imprisoned Islamic extremists should have their own segregated prison wings to prevent the radicalisation of more moderate inmates among Britain’s growing Muslim prisoner population.