HUNDREDS of British non-Muslims have been recruited by al-Qaeda to wage war against the West, senior security sources warned last night.
As many as 1,500 white Britons are believed to have converted to Islam for the purpose of funding, planning and carrying out surprise terror attacks inside the UK, according to one MI5 source.
Lord Carlile, the Government's independent reviewer of anti-terrorism legislation, said many of the converts had been targeted by radical Muslims while serving prison terms.
Security experts say the growing secret army of white terrorists poses a particularly serious threat as they are far less likely to be detected than members of the Asian community.
Since the 7/7 and 21/7 London bombings, police and intelligence services have had considerable success in identifying, disrupting and stopping extremist plots. As a result, groups such as al-Qaeda, Lashkar-e-Taiba and Harkat-ul-Mujahideen have been forced to change tack. Converting white non-Muslims has been one response.
The trend is well established in the United States. American-born Adam Gadahn is one of the FBI's top 10 most-wanted terrorists after converting to Islam and rising through al-Qaeda's ranks to become a prominent spokesman.
One British security source last night told Scotland on Sunday: "There could be anything up to 1,500 converts to the fundamentalist cause across Britain. They pose a real potential danger to our domestic security because, obviously, these people blend in and do not raise any flags.
"The exact figure of those who have converted to Islam and turned to terror is not precisely known. Not everyone who converts becomes radicalised and it may be that just two-fifths go down that path, but it remains a significant and dangerous problem."
Carlile said he was not aware of specific numbers, but confirmed to Scotland on Sunday that Whitehall was aware of the new threat and was actively tackling it. He said: "These people are an issue and are potentially very dangerous. There have been cases of non-Muslims converting before, and of these, Richard Reid, the so-called Shoebomber, is the most obvious example.
"They are more difficult to detect and the security services are right to place some focus on this issue."
Carlile said the majority of converts were targeted when they were in prison: "These (converts] are outside the standard type of profile which most police forces would have of a terrorist, which is male, young, and of Middle Eastern or Asian appearance. That is why they are so potentially dangerous."
Carlile added: "The Home Office has a lot of money, millions of pounds, which is being put forward for communities and fighting radicalisation. There is no question how tackling this issue is best achieved: it is achieved at a community level."
Security experts say radical Muslims in prison have become adept at identifying potential new recruits to their cause. Those in custody for the first time, the young and the lonely are particularly susceptible.
Initially, the approach is made to comfort, console and support, with very little reference, if any, to religion.
However, after several 'chats', the conversation will be turned towards the subject and, gradually, over a period of weeks or months, it is possible to complete the conversion.
Robert Leiken, director of the Immigration and National Security Programme and a specialist on European Muslims based at the Nixon Centre in Washington DC, said: "To me, the figure of 1,500 seems reasonable as many, perhaps less than a third, will actually go on to become radicals.
"New religious recruits always tend to be more zealous than those who have grown up with that specific religion."
Edwin Bakker, a Dutch-based security specialist, has studied at length the issue of radical conversions. He said: "The question is relevant and timely. Newcomers to Islam are extra-sensitive to perceived discrimination of Muslims and Islam-bashing.
"They feel they have to defend Islam – one of the essential concepts of Jihad – and they feel they have to prove themselves as newcomers."
But one of Scotland's leading Muslims disputed the claims of radicalisation, saying Islam's strict moral code made it unattractive to many westerners.
Bashir Maan added: "I do not know of any Islamist terror group in Scotland and, considering as a Muslim a person must pray five times daily, abstain from drinking (and] sex outside marriage, adhere to strict dietary and many other rules, it is impossible to convert to Islam a young person brought up in this very liberal society.
"I agree that the security services must be vigilant and keep their eye on everybody, but I think in this case they seem to be over-reacting."