Britain’s first prison designed to separate terrorists and extremists from other inmates is now operational, the government has said.

The Ministry of Justice announced on Thursday that it has populated a “separation centre” within a prison in County Durham, England.

The unit, on the grounds of HMP Frankland, is one of three planned centres which will eventually hold a total of 28 inmates. It has been running since last week.

The units are designed to keep the most dangerous prisoners from radicalising other inmates when they are in jail.

A press release announcing the new centres listed criteria for being sent there. Prisoners can be sent to the wings if:

    They have previously planned terror attacks They pose a risk to national security They have tried to persuade others to carry out terror attacks They "purposely undermine" prison security

Prison officials do not comment on which inmates are housed where, as a matter of long-standing policy. But a report by MailOnline claimed that hate preacher Anjem Choudary was one of the first inhabitants, alongside Michael Adebolajo, one of the men who murdered Fusilier Lee Rigby in Woolwich in 2013.

Announcing the new unit, prisons minister Sam Gyimah said: "Extremism must be defeated wherever it is found. The most dangerous and subversive offenders are now being separated from those they seek to influence and convert, an absolutely crucial element of our wider strategy to tackle extremism in prisons and ensure the safety of the wider public."

The decision to isolate high-risk offenders system follows a government report which highlighted the dangers of leaving religious extremist prisoners as part of the general prison population.

A report by Lord Ian Acheson published in August 2016 warned that it was common for prisoners jailed for terror offences to openly express and encourage support for ISIS among prisoners.

It also said extremist inmates were "acting as self-styled 'emirs' and exerting a controlling and radicalising influence on the wider Muslim prison population".

The other two planned centres, at HMP Full Sutton in Yorkshire and HMP Long Lartin in Worcestershire, are expected to open later this year.