A small number of Islamist inmates in England and Wales are proselytising some of the country's 12,500 Muslim prisoners and should be isolated within top-security prisons, according to an official review.

Ian Acheson, a former prison governor who wrote the report, called for "incapacitation" units to tackle the Islamist prisoners and said that the National Offender Management Service, which runs prisons, lacked a coherent strategy. His report found complacency among prison guards over the threat.

"There are a small number of people whose behaviour is so egregious in relation to proselytising this ... lethal nihilistic death cult ideology — which gets magnified inside prison, particularly when you have a supply of impulsive and often highly violent young men — that they need to be incapacitated from being able to proselytise to the rest of the prison population", Acheson told the Commons justice committee of MPs this week.

The outgoing Justice Secretary Michael Gove said he was "extremely sympathetic" to the plan to isolate the Islamists, The Times reported.

Acheson said that some of the extremists were in prison for reasons other than terror-related offences but had become radicalised while in prison. "The problem is serious but not out of control. There are a number of prisons where the problem is particularly serious," he said.

Outlining his plans for purpose-built units within high security prisons, Acheson added: "It is not about prisons for Muslims or prisons for terrorists. It is a nuanced response that holds out the possibility of redemption."

Acheson said that the review team had visited prisons in the Netherlands, France and Spain, where they were beginning to separate their extremist prisoners.

Gove said that the proposals would need the backing of the new home secretary, Amber Rudd, as the minister in overall charge of the government's counter-extremism policy.