(Photo:Simomos Petras monastery at Mount Athos/Daniel Flynn)

For many Orthodox it is the fulfilment of a long-held dream to visit the rugged Holy Mountain -- but not if you a woman. Women are completely banned from the 300 sq kilometre peninsula and any breach of this strict rule is a criminal offence in Greece punishable by up to two years in prison.

Omar Sheikh, a member of the Jaish-e-Mohammad (Army of the Prophet) organisation which has been linked to the bombing, is currently on death row in Pakistan for organising the kidnapping and beheading of the brilliant Wall Street Journal reporter Daniel Pearl in Karachi in February, 2002.
 
I had long since lost contact with Omar since we both graduated from Forest School in north London in 1992 and the sight of a heavily bearded Sheikh flanked by Pakistani police during the Pearl trial came as a shock. My jumbled memories of Omar were of a tall, lantern-jawed adolescent with dark-rimmed glasses, a serious but polite demeanour, a childish sense of humour but an unblinking, fearless appetite for a fight. Even as a boy, he spoke feverishly and often of "My Country" and praised the authoritarian and strictly Islamic regime of General Zia -- who ousted and killed Benazir Bhutto's father and helped the mujahedin throw the Soviets out of Afghanistan.

A tangle of contradictions, Omar's other great love aside from patriotism was arm-wrestling and the would-be Islamist would often be found in smoky pubs -- drinking only milk -- competing with his team.

We had both started at Forest School at the age of 11 and I remember he never cried at anything - unless he was angry with himself. He loved chess and often spent his lunch breaks pouring over a chess board with a group of friends who were mainly from Sri Lankan, Indian or Bengali families.

The son of a clothes merchant in Wanstead, north London, Omar lived in a nondescript house in a cul-de-sac, where he invited me for lunch after he returned from three years of schooling in Pakistan at the age of 16. Wary of England's influence, Omar's father sent him to study at Lahore's exclusive and disciplinarian Aitchison school -- he returned a junior boxing champion and full of stories of contacts with organised crime, gun battles in the ghettos of Lahore, visits to brothels. At the time I thought they were all tall stories - as the chess-lover that he was, Omar's conversation was full of bluffs and feints -- but now I'm not so sure. What I remember of our long lunch were Omar's fascination with girls and his shock at the liberal relations between young girls and boys in England.

In the sixth form, he became interested in economics, dreamed of going to study in the United States at Harvard, and even sat the SAT exams, and he went everywhere with a sturdy black plastic suitcase which weighed a ton (I think he carried weights around to pump up his muscles for arm-wrestling). He seldom had fights at school after he returned from Pakistan and had trained as a boxer, but he would often joke around by letting his fists fly within inches of your face as if he were shadow boxing.
 
Looking back, Omar's years in Pakistan were the first step in a transformation which was completed when he went to the London School of Economics and threw himself into the cause of persecuted Muslims in Bosnia. After a mysterious trip there at the end of his first year in 1993, Omar dropped out of his studies and his conversion to militancy began.
 
By the time of the Pearl kidnapping, Sheikh was already a high-profile militant: he had been detained in India in 1994 for the kidnapping of three Britons and an American in the volatile Kashmir region. Via our school, his lawyer asked if I would be willing to testify as a character witness at his trial, a request I turned down. In any case, I couldn't see what my testimony as a character witness could achieve, given that Omar appeared to have undergone an ideological transformation by that stage.

Finally, Omar walked free in 1999 when Islamist militants hijacked an Indian Airlines flight with 155 people on board from Kathmandu, forcing it to land in Kandahar in Afghanistan. The Indian government exchanged Omar and two other prisoners in return for the release of the passengers and crew.
 
In many ways, Omar's Westernised identity made him a precious commodity in the militant world. In his book "Who Killed Daniel Pearl?", left-wing French intellectual Bernard-Henri Levy cites evidence Sheikh had spent time with Osama bin Laden in Afghanistan and the al Qaeda founder referred to the genteel and well-educated economist as "my favourite son".
 
Levi also cites evidence Sheikh was a conduit for funds from the head of Pakistan's fractious but powerful military intelligence agency ISI to the pilots of the 9/11 planes in the United States. The Wall Street Journal's Pearl was investigating the embarrassing allegations that one of the U.S. government's most important allies in fighting terrorism was actually linked to the New York attacks at the time he was kidnapped -- a charge Pakistan has denied.
 
Sheikh appears to have spent a week in the hands of the ISI before being turned over for trial for Pearl's killing, and Pakistan has steadfastly refused to hand him over to US authorities. Sheikh remains a mysterious figure: Pakistan's former president Pervez Musharraf alleged he was actually working for British intelligence and downplayed his significance.
 
Even before the July 7, 2005 bomb attacks on London, Omar was an early reminder of the fragmented and conflicted identity of some young Muslims in England. Indeed, the Jaish-e-Mohammed group, linked to Pearl's beheading and the Islamabad bombing, is alleged to receive much of its funding from Pakistanis living in Britain. While Omar had a reckless longing for adventure which propelled him along his path to radicalism, he also shared with many second-generation immigrants to Britain a longing to belong and he struggled to find anything in British society with which he could strongly identify.

Can Britain be called a functioning multi-cultural society? Has the appeal of armed Islamist groups been heightened by Britain's military intervention in Muslim states like Iraq and Afghanistan? And as the United States frets about the risks of young men with western passports being trained up by militants in Pakistan's tribal areas to carry out suicide bombings at home, what can be done to prevent them from being drawn into militant circles?