British Muslim extremists are increasingly switching from Pakistan to Somalia to receive training in militant camps with the aim of carrying out attacks in this country, according to the head of MI5.
Jonathan Evans said yesterday there was deep concern that "it is only a matter of time before we see terrorism on our streets inspired by those who are today fighting alongside Al Shabaab, an Islamist militia in Somalia".
While it has been known for some time that members of the Somali diaspora in the UK had been back to their homelands to join insurgents, others including those of Pakistani, Bangladeshi and North African extraction are now taking the same route. Some have been killed in the fighting there, but others have returned to Britain following lessons from the Al Shabaab group which is believed to have links with Osama bin Laden.
Mr Evans, the Director General of the Security Service, said yesterday that the number of bombing plots in the UK linked to Pakistan had fallen from 75 per cent to about 50 per cent following action against al-Qa'ida's senior leadership in the country's tribal belt. But, he continued: "The reduction is also partly as a result of increased activity elsewhere. In Somalia, for example, there are a significant number of UK residents training in Al Shabaab camps to fight in the insurgency there. Al Shabab, an Islamist militia, is closely allied with al Qa'ida and Somalia shows many of the characteristics that made Afghanistan so dangerous as a seedbed for terrorism in the period before the fall of the Taliban."
As well as Islamists, the UK also faced threats from dissident Irish republicans; convicted terrorists about to be freed from prisons in this country after serving their sentences, Mr Evans said.
Although MI5 is expected to undergo financial cuts along with other government departments, Mr Evans is said to accept that this is inevitable in the current economic climate and is not seeking extra resources.
In a speech last night to the Worshipful Company of Security Professionals, Mr Evans repeatedly stressed the role played by control orders, which restrict movements of suspects, in combating terrorism.
Mr Evans has briefed David Cameron on the use of control orders. The coalition Government is in the process of making decisions on whether they should be repealed. While some senior Tory ministers say they were unaware of the gravity of the security situation while in opposition, the Liberal Democrats have declared that the rules infringe civil liberties and should be got rid of.
Officers in MI5, MI6 and the police's anti-terrorist branch hold that the measures fulfil a "useful function" while accepting, they say, that it is ultimately a political matter. Mr Evans said: "Whilst we are committed to prosecutions wherever possible it is a sad fact that for all sorts of good reasons terrorist threats can still exist where the English criminal justice system cannot reach. The government cannot absolve itself of the responsibility to protect its citizens just because the criminal law cannot, in the particular circumstance, serve the purpose.
"Each month at present we receive several hundred pieces of information that might be described as new 'leads' to violent extremism and terrorism relevant to the UK ... The secret nature of this struggle makes it harder for those not directly involved to understand some of the skirmishes that come into the public domain: for example, the control orders, the immigration cases and criminal cases."
He said terrorist plots were foiled "by arrests, by immigration action, by special measures such as control orders or in some other way. Our aim is to reach a position of assurance where any threat is identified and action taken to disrupt it before any harm is done, and particularly before there is an imminent danger to the public."
Some suspects remained a threat despite going through the legal system and serving prison terms in the nine years since 9/11, Mr Evans said.
"Unfortunately we know that some of those prisoners are still committed extremists who are likely to return to their terrorist activities and they will be added to the cases needing to be monitored in coming years."
Most of that "imminent danger" came from Islamist groups. But Mr Evans stressed the threat now being posed by dissident republicans in Northern Ireland.
The Independent had highlighted how counter-explosives specialists, needed in Afghanistan, are now having to be sent there. The membership of the dissident groups was estimated to be around 200 two years ago, but it has now grown to about 600, with new recruits continuing to join.
Mr Evans said: "While at present the dissidents' campaign is focused on Northern Ireland we cannot exclude the possibility that they might seek to extend their attacks to Great Britain as violent republican groups have traditionally done."