© Provided by Local News RSS EN-GBShamima Begum when she was 15 and fled to join IS (PA)
MI6 boss Alex Younger today warned that Britons returning from Islamic State were "potentially very dangerous" and stressed public safety must be the first consideration.
The head of the Secret Intelligence Service also spoke out against "triumphalism" as the terror group is being crushed territorially in Syria and Iraq, stressing that destroying it was a generational battle.
Mr Younger did not want to comment specifically on the case of Shamima Begum, 19, from east London, who revealed yesterday she wants to come home despite expressing no regrets at becoming an jihadi bride.
But Mr Younger warned of the risk posed by Britons coming back to the country having joined IS. © PABritish IS bride 'has Stockholm syndrome', say family
"They are likely to have acquired both the skills and connections that make them potentially very dangerous and also experienced extreme radicalisation, either in their journey to that place or when they are there. That fact needs to be uppermost in our minds. © Provided by Independent Digital News & Media LimitedHead of MI6 Alex Younger (EPA)
"As we approach this admittedly extremely complex and difficult problem, public safety is the first thing that we will consider.
"It follows from that that anyone who has put themselves in this situation can expect to be questioned and investigated and potentially prosecuted if they return to our jurisdiction."
© PAAmira Abase Kadiza Sultana and Shamima Begum were pictured at Gatwick airport
Watch: Interview with Shamima Begum, Bethnall Green girl who fled to Syria
Mr Younger emphasised that the so-called IS caliphate was now in its "end game", with the extremist militants clinging to the last square mile of land that they hold in eastern Syria in the village of Baghuz.
The few hundred remaining IS fighters are being targeted by precision-strikes in a US-backed operation which was expected to clear them out shortly, with US President Donald Trump poised to declare a victory.
However, in a rare interview with journalists at the Munich Security Conference, Mr Younger said: "We are not triumphant because I think from triumphant you get to hubris. © Provided by Local News RSS EN-GBFighters from the Syrian Democratic Forces (SDF) gather around a humvee armoured vehicle near the battered Islamic State-held holdout of Baghouz in the eastern Syrian province of Deir Ezzor (AFP/Getty Images)
"The reality is this is a societal, generational problem that we face in the West and it can only be addressed at that level.
"So, of course, the military defeat of the 'caliphate' does not represent the end of the terrorist threat. You can't use military force to kill an idea but you can use it to denigrate and disrupt the sharpest end of the problem."
In the interview before talks with Bruno Kahl, president of Germany's Federal Intelligence Service, and Bernard Emié, head of the French DGSE national foreign intelligence agency, Mr Younger also stressed that, amid Brexit turmoil, Britain had an "unconditional" security offer to Europe.
"There are people alive in our three countries today because of terrorist attack plans that we have successfully disrupted, showing the value and importance of co-operation to all sides," he said.
He emphasised the importance of the strategic partnerships between the UK and its allies to counter hybrid threats from Russia and other nations and terror groups, adding: "We will show steel in defence of our citizens and our interests."
Related: US forces in Syria (Reuters)
He believes Russia is seeking to target elections in the West to "reduce the quality of political trust in institutions and discourse". Pledging an "assertive" response, Mr Younger added: "We have been really, really clear with them that whatever they think they are trying to achieve with this concerted campaign of covert and overt action to denigrate our quality of institutions and alliances, it's not going to work, it's going to come at too high a cost."
Discussing whether there was still a threat to Novichok poisoning victims Sergei and Yulia Skripal, he explained: "We assess that there is a standing threat from the GRU and the other Russian intelligence services and very little is off-limits." © GettyHome Secretary Sajid Javid
Mr Younger signalled he did not favour an outright ban on Chinese telecoms equipment giant Huawei being involved in a 5G network in Britain, but warned against monopoly suppliers in key areas of national infrastructure.
The spy chief also warned of the re-emerging threat posed by al Qaeda.
The capture of Baghuz and nearby areas would mark the end of a devastating four-year global campaign to end Islamic State's hold on territory in Syria and Iraq, their so-called caliphate.
At the height of the group's power in 2014, IS controlled nearly a third of both Iraq and Syria.
Related: Inside the IS tunnel network (Reuters)
Mr Trump has said the group is all but defeated, and announced in December that he would withdraw the 2,000 US forces from Syria.
But Mr Younger warned: "As you would expect, Daesh (IS) is a resilient organisation and it is reorganising essentially returning to it's natural state as an asymmetric, transnational terrorist organisation.
"We see it therefore morphing, spreading out ... within Syria but also externally ... this is the traditional shape of a terrorist organisation."
"Al Qaeda, which has always been in a rivalry, an almost zero-sum relationship with Daesh, has undergone a certain resurgence as a result of the degradation of Daesh and is a force that should also be taken seriously.
"It's definitely not down and out."
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