LONDON (AP) — Britain has announced plans to house Islamist extremists in separate units in prison after a review found that some charismatic prisoners were radicalizing the wider Muslim population while incarcerated.

The government-ordered study concluded that “cultural sensitivity” among National Offender Management Service staff toward Muslim prisoners went too far and “could inhibit the effective confrontation of extremist views.”

The findings of the review released Monday recommended introducing the specialized units in order to stop a small number of individuals from being able to “proselytize” to other inmates.

Some 12,633 Muslims were in prison in England and Wales at the end of June, compared to 8,243 a decade earlier. Of the 147 people in prison for terrorism-related offences at the end of March, all but 10 considered themselves to be Muslim.