Northern Ireland could become a back-door route for Isil terrorists to launch an attack on the UK, security sources fear.
The alarm has been raised with ministers that the region is an easy target for Islamic groups seeking to launch plots in the UK because the Prevent anti-terror strategy does not apply and Police are focused on sectarian violence instead of external threats.
Fears that terror cells could base themselves in the Republic of Ireland to plan an attack and then slip across the border – which is not closely monitored – have added to serious concerns in Whitehall.
Two senior Government ministers admitted there is a problem with border security and warned there is a “blind spot” to Islamic terrorism in Northern Ireland, making the UK mainland vulnerable.
One minister warned: “There is an issue to do with the open border because if you can get into southern Ireland you have got border-free access in to the UK.
“So someone could come from abroad or be radicalised in Ireland and move easily across the border in to the UK.”
A parliamentary report published earlier this year revealed that people can enter the UK via the Republic of Ireland or Northern Ireland without being checked by UK Border Force computers.
The Public Accounts Committee found: “The Department told us it checks 100% of passports at the border, but this is not the case. It does not, for example, check passports of those entering the UK via land or sea from the Republic of Ireland or all those entering via general aviation and general maritime routes.”
An earlier report from the National Audit Office admitted that there are “no reliable estimates” for the number of people entering the UK via these routes.
Lenient border controls and the fact that Prevent, the strategy which aims to stop people becoming radicalised and halt plots before they take place, does not apply in the region, have led to worries that possible threats are not being picked up or tracked.
A second senior Government minister said that jihadi threats “do not get the same attention” as sectarian violence because of the country’s long history of home-grown terrorism.
Sensitivities around how the Westminster Government sets terror policy in Northern Ireland have also meant attempts to tighten up border control and monitor potential jihadist terror plots are difficult.
The senior minister said: “There is a fear that islamist terrorists will use Northern Ireland as a back door to fulfil their aims of attacking the United Kingdom because there is a complete blind spot to that kind of activity.
“The police and security services there have so much on their plate tackling domestic terrorism that jihadism does not get the same attention.
“The Prevent strategy we have in the UK doesn’t apply in Northern Ireland because these things are devolved, so there are question marks over counter-radicalisation as well and whether enough is being done to keep tabs on possible plots.
“Unfortunately it’s only a matter of time before groups like IS realise Northern Ireland could be an easier route for them to attack the UK.”