THE country’s most dangerous terrorists will be held in a specialist unit within a North-East prison.

It is understood work is advancing at the high-security HMP Frankland, at Brasside, near Durham, which has been earmarked for a "prison within a prison" - to isolate Islamist terrorists from other criminals.

The Northern Echo:

TERRORISTS: HMP Frankland inmates Michael Adebolajo, Omar Khyam, Dhiren Barot and Tanvir Hussain and Westminster terror attacker Khalid Masood

It follows a Government report which found Britain’s “most subversive extremist prisoners” should be jailed separately to tackle the "growing problem" of committed jihadis radicalising fellow inmates.

Ministers' concerns rose after it emerged that Westminster terror attacker Khalid Masood may have had an "abrupt religious conversion" while in jail for stabbing incidents.

HMP Frankland – one of eight high security prisons in the country - is already home to a number of the UK’s most notorious terrorists.

In recent years, it has been home to Tanvir Hussain, who planned to down flights from Heathrow to America using liquid bombs hidden in soft drink bottles; Dhiren Barot, who masterminded a plot to explode a radioactive “dirty bomb” in the UK and Omar Khyam, convicted of planning to blow up Bluewater shopping centre in Kent.

More recently, Michael Adebolajo, who murdered Lee Rigby on the streets of London, was transferred to Frankland amid fears he was attempting to radicalise inmates in Belmarsh.

In 2015, a copy of the Al Qaeda magazine Inspire was uncovered during a cell search.

The Government revealed plans in August to hold the “most subversive extremist prisoners” in specialist units to allow greater separation from the rest of the prison population

A Ministry of Justice spokesperson said: "Islamist extremism is a danger to society and a threat to public safety — it must be defeated wherever it is found. We are committed to confronting and countering the spread of this poisonous ideology behind bars.

"Preventing the most dangerous extremists from radicalising other prisoners is essential to the safe running of our prisons and fundamental to public protection.”

The move follows a review by former prison governor Ian Acheson into Islamist extremism in UK prisons.

One of his principle recommendations was to hold a small subset of extremists who present a “particular and enduring risk to national security through subversive behaviour, beliefs and activities” in units removing them from the general prison population.

Prison staff have warned that lessons must be learned from past attempts to deal with terrorism.

Steve Gillan, general secretary of the Prison Officers Association, said: "We as a union are sceptical that segregating these people is not the answer.

"We have vast experience of that in Northern Ireland and it didn't work there, it made the situation worse.

"We remain neutral and will watch to see what impact it will have. The security of our members will be paramount at all sites."

Jackie Marshall, a representative of the POA's national executive committee, said the union was happy that appropriate staffing levels had been agreed.

She said: "It's due to open within the next couple of months. Appropriate staffing levels have been agreed.

"There are no concerns from staff at Frankland. Until things are up and running we never really know."

The MoJ said no final decisions had been made on timings or staffing levels.

Durham City MP Roberta Blackman-Woods said: “It’s really important that prisons address the issue of radicalisation of people when they are in prison.

“If this unit can help in the wider de-radicalisation and prevent strategy then I think it’s a good thing and its a recognition that there’s an issue that needs to be tackled.”

She added: “On its own it’s not enough and we know that. There has to be much, much more in the overall strategy to deal with radicalisation.”