Britain said Thursday it had begun housing Islamist extremists in separate prison units to prevent them radicalising other inmates, as it grapples with a mounting terror threat.
A new "separation centre" has been opened at Frankland jail near Durham, northeast England, the interior ministry said.
It is first of three centres which together will have a capacity of 28 inmates.
"The most dangerous and subversive offenders are now being separated from those they seek to influence and convert," said the minister for prisons, Sam Gyimah.
The move was recommended by a review into Islamist extremism in prisons published last year, which highlighted similar schemes in the Netherlands, France and Spain.
It found some "charismatic" prisoners were acting as self-styled "emirs" and exerting a controlling and radicalising influence on the wider Muslim prison population, and also found some "aggressive encouragement" to convert to Islam.
The review also highlighted incidents of unsupervised collective worship, intimidation of prison imams and the availability of extremist literature.
The interior ministry said 4,500 frontline prison staff had received specialist training on how to identify and challenge extremist views, adding that new recruits would receive the training as standard.
Britain has suffered a string of terror attacks in recent months, and police say they have foiled 18 plots since 2013.
Official figures show there were 186 people in custody for terrorism-related offences and domestic extremism on March 31 this year, up 15 percent on the previous year.
In the year to March, 304 people had been arrested for terrorism-related offences -- the highest number since records began in September 2001, and an annual increase of 18 percent.
Of these, 108 were charged and 88 were released on bail pending further investigation.
In the same year, 70 terrorism-related trials were completed by state prosecutors -- up 55 percent from 51 in the previous year, with 68 resulting in convictions.