“I dreamt of coming to the West,” he says. “I thought the West was a paradise where you could do everything you wanted. I was not a good Muslim.”

The suit was smart, the hairstyle fashionable, and in his pocket, he says, was the offer of a place to study civil engineering at a British university.

Mostafa’s ambitions were not only academic: he also, apparently, hoped that he would soon be enjoying the company of Western women.

Fast-forward 24 years and Mostafa is now better known as “Sheikh” Abu Hamza al-Masri, 44, the one-eyed, hook-handed imam of Finsbury Park mosque.

The fundamentalist cleric has been widely vilified for heaping praise upon Osama bin Laden and the September 11 hijackers, and last week his mosque was the target of a raid by 150 police.

Furthermore, he is wanted for questioning by police in Yemen investigating a terrorist plot, and a grand jury in Seattle is deciding whether to indict him over alleged plans to set up a terrorist training camp in Oregon.

The Home Office has been unwilling to extradite him to Yemen, however, as there are fears that he would not be given a fair trial. Nor has the Government been able to deport him to Egypt, as he has been a British citizen since his marriage, in May 1980, to an Englishwoman. Last night that impasse appeared to have been broken, when it was discovered that the marriage was bigamous, and therefore void.

His bride, Valerie Traverso, then 25, was already married, and had been for the previous nine years. Ms Traverso’s first marriage did not end in divorce until July 1982, by which time she had been bigamously married to Abu Hamza for more than two years.

Last night Home Office officials were examining the discovery before taking a decision on Abu Hamza’s status.

Scotland Yard is also likely to investigate the marriage — bigamy is a criminal offence under the 1861 Offences Against the Person Act and punishable by up to seven years in prison.

It is unclear, however, whether Abu Hamza knew that his marriage was bigamous, or that he could be stripped of his British citizenship.

Abu Hamza, the son of an Egyptian Army officer named Kamel Mostafa, was 19 or 20 when he first arrived in Britain. He is said to have been exceptionally fit at that time: he says that he lost his hands and left eye while working for the Afghan Mujahidin in 1993, when a mine exploded while he was clearing a path.

Abu Hamza claims to have gained an honours degree in 1982 from the University of Brighton, which was then a polytechnic, but the university said yesterday that it could find no record of his attendance.

On May 16, 1980, he was married under his real name, Mostafa Kamel Mostafa, at Westminster Register Office, to Ms Traverso, a window dresser from Chelsea. Although he has hinted that he was employed as nightclub bouncer at the time, his occupation is recorded on his marriage certificate as a hotel receptionist.

His bride recorded her marital status as “spinster”, despite having been married for the previous nine years to a builder’s labourer called Michael Macias, by whom she had two children.

Records held at Wandsworth County Court in South London show that the marriage did not end until July 13, 1982, when Mr Macias obtained a divorce. The grounds for the divorce are unclear.

Under the terms of the Marriage Act 1949, Abu Hamza’s marriage will now be considered void, according to family law experts.

By the time she was divorced from Mr Macias, Ms Traverso had already given birth to Abu Hamza’s oldest child, Mohammed. Their marriage ended in August 1984.

Abu Hamza appears to have embraced fundamentalist Islam and adopted his present name in the late 1980s. He began preaching at Finsbury Park six years ago, but became embroiled in a struggle for control of the mosque with its trustees after he praised Osama bin Laden after September 11.

A number of suspected terrorists are known to have worshipped there, including Richard Reid, the so-called shoe bomber, and Zacharias Moussaoui, known in the United States as the 20th hijacker.

Abu Hamza lives in Shepherd’s Bush, West London, where he is thought to have been paid £100,000 in welfare benefits over the past three years, including three types of disability payments, income support, housing benefit and help with fuel bills.

Meanwhile, Ms Traverso, now Valerie Fleming, is living in Stevenage, Hertfordshire, with her fourth husband, and has refused to speak about her marriage to Abu Hamza. Their son Mohammed, who is now 21, served three years in a Yemeni jail after he was convicted of plotting terrorist attacks on British targets. He is now living with his father and is also believed to be claiming welfare benefits.

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