The radicalisation of Muslims in British prisons could produce hundreds of home-grown terrorists as the UK faces threats from lone bombers and assassins sent out to try their luck, experts have said.
Large-scale coordinated attacks are being replaced by highly-motivated but poorly trained individuals operating with the expectation that eventually one will succeed, a report in the Royal United Services Institute (Rusi) journal found.
The UK has more to fear than any other western country from home-grown terrorists and the conditions are all there for a series of attacks to begin at any time, the report for the defence and security think-tank said.
Its authors, Rusi director Michael Clarke and research fellow Valentina Soria, said estimates showed one in 10 of the 8,000 Muslim prisoners in high-security institutions in England and Wales were "successfully targeted" by radical jihadists. They wrote: "Perhaps some 800 potentially violent radicals, not previously guilty of terrorism charges, will be back in society over the coming five to 10 years."
Coupled with a foreign policy that "serves to focus alienation and resentment", the phenomenon of home-grown terrorism in the UK is growing, they said, adding: "The natural reaction to improved counter-terrorist operations is for jihadist attacks to evolve towards more individual efforts."
They continued that "a powerful al-Qaida media campaign" would make them "appear as dramatic and threatening as earlier attacks".
They said: "If lone bombers and assassins are being sent out to try their luck... the key variable will be the effect these lone or spontaneous attempts have on the motivation of others to join the jihad. Lone killers will always exist and some of them will succeed. The key question is whether their acts remain that of individuals or become part of a structural phenomenon."
Under a new generation of leaders such as Anwar Al-Awlaki, considered one of the world's most wanted terrorists, "it appears that high motivation is followed by fairly rudimentary training", the authors wrote, pointing to the apparent lone bomber behind the Times Square car bomb in New York in May.
The Rusi report went on: "The possibility of attacks now hangs over all major sporting events from the Commonwealth Games in India and the 2012 Olympic Games in London, to all future signature events such as football World Cup tournaments."
For the British public, it warned, the "greatest danger is public complacency".