The Ministry of Justice has blocked a study examining why so many convicts and prisoners in the UK are converting to Islam and turning to extremism.

A so-called “corporate culture” in the government department was blamed for the move, with officials allegedly worried about what the academic study might unearth or reveal.

Many of the UK’s homegrown extremists have converted to Islam in jail, including the Westminster terrorist attacker Khalid Masood, with some prisons allegedly controlled by Islamic gangs and prisoners forced to covert for their own protection.

The proposed three-year study was supported by Max Hill, the independent reviewer of terrorism laws, but the prison service did not want outsiders studying such a sensitive area, The Times reports.

“The scale of radicalisation should not be overestimated but in certain prisons it is certainly growing,” a source told the newspaper.

Adding: “The corporate culture of the service is defensive and they will have been concerned about what this proposed project will discover.”

Others sources claimed that the study could have revealed that inmates are converting because of cultural pressure and to get better food and avoid gang violence.

Muslim Terrorists Are Running Whole Prison Blocks Under Sharia Law https://t.co/CoWC2JdRX1 pic.twitter.com/XNQ4rvthDL — Breitbart London (@BreitbartLondon) April 5, 2016

Matthew Wilkinson, the principal investigator, said: “Prison governors want our independent research to discover what is actually happening on their prison wings; not what is feared or suspected to happen.”

The number of Muslim in jails in England and Wales has increased from 5,500 in June 2002 to 12,894 at the end of June this year.

Earlier this year, it was revealed that 228 inmates in Britain had been locked up for terrorist offences – with 82 percent of those being classed as holding Muslim views.

In late 2015, the Prison Officers Association (POA) found that a growing number of non-Muslims are being forced to pay a “protection” tax, or “jizya” unless they convert to Islam.

The former chief inspector of prisons Nick Hardwick later warned that Islamic extremists are increasingly using British jails to recruit inmates as potential terrorists.

The POA has admitted that there is a “real problem” with inmates being radicalised with prison sources adding that imams with extremist views were being allowed to preach in British prisons because of a “shambolic” vetting system.

Counter-extremism think tank Quilliam said at the time: “We are aware of several individuals employed by the prison service who have links to extremist groups.

“Prisons are incubators of extremism. Young men are going in petty criminals and coming out extremists.”