Number of extremists being monitored in the UK has risen to 3,000

British counter-terrorism officials are monitoring 3,000 extremists in the UK that they fear could commit acts of domestic terror or become future “Jihadi Johns”.

Many will never have travelled abroad or been official members of terrorist organisations, underscoring the growing problem facing intelligence and security agencies across Europe in tracking radical communities of home-grown terrorists.

The disclosure follows the unmasking of Londoner Mohammed Emwazi this week as the hooded murderer responsible for some of the most barbaric killings perpetrated by the Islamic State of Iraq and the Levant, or IS.

Significantly higher

The 3,000 figure is significantly higher than previous estimates. In late 2007,

Jonathan Evans

, then director-general of MI5, Britain’s domestic intelligence agency, said the security service was monitoring 2,000 people.

The number of so-called SoIs – subjects of interest, as potentially violent extremists are known in MI5 parlance – had been stable until recent months, but the rise of IS has expanded their ranks.

Senior Whitehall security officials said there was real concern over the impact social media was having on radical individuals in Britain and its ability to magnify the appeal of jihadism in the Middle East.

The focus of counter-terrorism efforts in Europe until now has been on preventing citizens from travelling to Syria and Iraq to join terror groups. An estimated 3,000 Europeans have travelled to fight there, among them more than 500 Britons. But individuals who remain at home are increasingly being seen as high priority targets for monitoring as the incidence of “lone wolf” terror attacks grows.

They are becoming harder to track too, British officials say, because they are less likely to be members of groups or well-connected networks. One senior security officer described the problem as like trying to follow the random “brownian motion” of particles in a teapot.

“There have always been a lot of people [under watch]. But the perception for a long time was that the numbers had plateaued,” said Raffaello Pantucci, director of international security studies at the think-tank Rusi.

“Now there is a whole new layer on top of that because the noise from IS in Syria and Iraq is so loud it is attracting others.” – (Copyright The Financial Times Limited 2015)