War against al-Qaeda in Africa could last decades Sources have confirmed that 28 British nationals and one UK resident were involved in the incident, which began last Wednesday. All 22 British survivors were back in Britain on Sunday and were undergoing intensive debriefing by the Foreign Office and MI6. Of the remaining six, three have been confirmed dead, and three are missing, presumed dead. Algerian officials on Sunday warned that their initial estimate that 23 hostages had lost their lives was likely to increase after the discovery of 25 charred bodies inside the gas plant. As the Algerian government announced that the worst terrorist hostage-taking in recent years was finally at an end, fresh information came to light, including: Out of the 32 hostage-takers, up to five were reported to have been captured alive by the Algerian special forces team that stormed the gas plant last week; Up to five of the militants who took part in the attack on the plant were employees there, raising fears of an inside job or infiltration by extremists; Mokhtar Belmokhtar, an extremist linked to al-Qaeda, on Sunday released a video taking responsibility for the "blessed operation," which he said was a response to the French military intervention in Mali, which borders Algeria to the south. Speaking at Chequers on Sunday, Mr Cameron acknowledged that the terrorist threat in North Africa had grown and he predicted a prolonged struggle to meet it. "It will require a response that is about years, even decades, rather than months and it requires a response that is patient, that is painstaking, that is tough but also intelligent, but above all has an absolutely iron resolve; and that is what we will deliver over these coming years," he said. William Hague, the Foreign Secretary, signalled that could mean directing more of Britain's growing aid budget to countries in the region. There is "no all-military solution" to the problem, he said. Western intelligence agencies have warned for several years that al-Qaeda-inspired groups are spreading in Africa as it becomes harder for extremists to operate in countries such as Afghanistan and Pakistan. However, British diplomatic and intelligence coverage of many countries in the Sahel region has traditionally been limited, since France, the former colonial power, has taken the lead. That weakness is now being questioned in Whitehall in the wake of the Algerian hostage crisis and the military conflict in Mali. The Prime Minister will brief MPs on events in Algeria and Mali on Monday and will on Tuesday convene his National Security Council for a "strategic" overview of Britain's engagement with the region. Greater international support for democracy and security in the Sahel countries will now be a focus of Britain's presidency of the Group of Eight this year, Mr Cameron indicated. Speaking on Sky News, Mr Hague accepted that the extremist problems of the region had been "gathering for some years" and said that part of the answer is more support for economic and political development in the area. "There is no military-only solution to all of this and that is why now we have to work with all the countries in that region to try to improve their political stability and their economic prospects, as well as working with them closely on counter intelligence to deal with the sorts of people who have launched this attack," said Mr Hague. British officials believe that one of the root causes of instability in the region is the fragility of Mali, where the northern Tuareg people are not reconciled to the southern-based government. Mr Hague said Britain will consider any French request for more help, such as aircraft, but will not deploy ground forces because the British Army is already "stretched." Some analysts have suggested that the fall of Muammar Gaddafi in Libya has contributed to instability in the region by dispersing large numbers of fighters and weapons previously controlled by his regime. Mr Hague admitted that there have been regional "spin-offs" from the British-backed intervention in Libya, but insisted: "Those could even have been worse had we not intervened." Ministers, including Mr Cameron, had earlier in the crisis expressed disappointment with the Algerian government's handling of the situation, including its refusal of British military assistance and its failure to give other nations advance notice of the rescue operation. But the Prime Minister and Mr Hague both softened their tone on Sunday, praising the Algerians. Mr Cameron said Britain should thank the Algerian government and remember that their soldiers had died in the rescue operation. Mr Hague said Britain should show "sympathy and solidarity" with the government and people of Algeria. The Foreign Secretary added that the Algerians had moved quickly to intervene because they believed that the lives of all the hostages were in "great and immediate danger," as the hostage-takers were planning to blow up the entire gas complex. France also defended the Algerian response to the situation. Laurent Fabius, the French foreign minister, said he was "shocked" at criticism of the Algerians over their response. "Everyone would have wanted for all the terrorists to be rendered harmless and for all the hostages to be saved," he said. But we understand well the difficulty when you are dealing with dozens of fully armed terrorists. One US citizen died at the gas plant. President Barack Obama also backed the Algerians. "The blame for this tragedy rests with the terrorists who carried it out," he said. The United States on Sunday warned its citizens of a "high threat" of fresh terrorism, including kidnappings in Algeria. Family members of US diplomats in the country have been encouraged to leave. It emerged last night that the leader of the al-Qaeda gang had indicated that he had been in contact with British officials during the crisis. In a radio conversation between Abdel Rahman el-Nigeri and Algerian special forces, a recording of which was released last night, the terrorist said: "I have spoken to the British but they are far away (from a solution) ." The recording was believed to have come from one of the workers at the site. However, Whitehall sources last night denied there had been any contact.