Islamic terrorists could be from any race, warns secret MI5 report

The internal study of hundreds of known and suspected radicals says it is difficult to identify those most likely to commit atrocities as they often have well-paid jobs and families and are 'demographically unremarkable'.

The Security Service report concludes that the vast majority are British nationals or in the country legally.

Slipping under the radar: The July 7 bombers arrive at Luton station to head for London for their suicide attacks. Future terrorists may be no easier to identify, MI5 warns

It says half are born here. The rest includes people who originally came to study or to join family or for economic reasons, as well as asylum-seekers who had fled oppressive regimes or violence. Many of these only became radicalised years after arriving.

Very few have come from highly religious households and most only practise their faith occasionally. The proportion of converts is above average.

Some are even known to have taken drugs, drunk alcohol and visited prostitutes.

But they are not especially prone to mental health problems or pathological personality traits.

They come from ethnic backgrounds as diverse as Pakistani, Middle Eastern and Caucasian.

Most have become radicalised in their early to mid-20s but a significant minority have not done so until later. Those over 30 are just as likely to have a wife and children as to be loners with no ties.

Radical clerics are also playing less of a role now in radicalising future terrorists, according to the 'restricted' briefing note, published in the Guardian today.

The research was carried out by the security service's behavioural science unit and involved analysis of several hundred people linked to violent extremism through activities ranging from fundraising to planning suicide bombings in Britain.

Overall they are 'a diverse collection of individuals, fitting no single demographic profile, nor do they all follow a typical pathway to violent extremism', the study says.

MI5 praises mainstream Islam, stating there is evidence that a well-established religious identity actually protects against violent radicalisation.