Global terrorism

1,500 suspects arrested in more than 50 countries since 11 September Potential al-Qaeda trained terrorists estimated to top 10,000 US investigators linked the 19 hijackers to at least 63 countries More than 130 terrorism-related arrests in UK since 11 September Scotland Yard say "substantially more" than 100 Britons linked to Bin Laden Three Britons named among Camp X-Ray prisoners

Officers say there are probably more than 100 Britons actively supporting al-Qaeda, while the chairman of Brixton mosque, Abdul Haqq Baker, has said there could be as many as 1,000 extremist Muslims in the UK and 100 potential suicide bombers.

On 29 January six people suspected of raising funds for Muslim militant groups were arrested after a series of raids across Teesside and Darlington.

The men are also suspected of providing logistical support to extremist groups although police said the arrests were not linked to the 11 September event and the men are not thought to be members of the al-Qaeda network.

In recent days the spotlight has also turned on Tipton, in the West Midlands, from where two British Camp X-Ray prisoners - Shafiq Rasul and Asif Iqbal - are said to have been recruited to a hardline Islamic group.

Click here to see a map of UK terrorism links

British officials have also confirmed that another man believed to be from the West Midlands is being held by US Forces in Afghanistan. Ruhal Ahmed is being detained in Kandahar.

The presence of a third Briton, Feroz Abbasi, 22, from Croydon, south London, at Camp X-Ray was confirmed last week.

Foreign law enforcement agencies have believed for years that Britain is acting as a covert breeding ground for extremists and sympathisers of Osama Bin Laden.

The allegations of Hassan Butt, a Pakistan-based activist who claimed Britons recruited for the Taleban would launch attacks in the UK, have only served to heighten such fears.

Zacarias Moussaoui, alleged "20th hijacker", lived in UK

Zacarias Moussaoui, the first person to be charged over the 11 September attacks, is alleged by the US to be the "20th hijacker" and to have been a member of an al-Qaeda cell in south London.

Also thought to have been involved in the same cell - and of being an active al-Qaeda operative - is Richard Reid, the Briton accused of trying to blow-up a transatlantic flight with explosives hidden in his shoe.

Mr Moussaoui - and other young Muslims suspected of becoming al-Qaeda conspirators - is believed to have been influenced by Jordanian-born cleric Sheikh Omah Abu Omar, more commonly known as Abu Qatada.

Investigators in both the US and Spain have accused him of being a key envoy of Osama Bin Laden in Europe.

Baltasar Garzon: Accused Abu Qatada

Baltasar Garzon, a National High Court judge charged with leading Spain's al-Qaeda crackdown, said Abu Qatada - whose whereabouts are unknown - was "the spiritual head of the mujahideen in Britain".

Mr Garzon has also alleged regular contacts between the cleric and a Spanish-based counterpart accused of being directly linked to the 11 September attacks.

Abu Qatada denies any link to any terrorist organisation, although he has expressed an admiration for Bin Laden.

A crucial figure for intelligence services struggling to piece together al-Qaeda's organisation is Algerian Djamal Beghal, whose British connections are also strong.

Picked up by police in Dubai last July, he apparently confessed - amid allegations of torture - to meeting Bin Laden, recruiting for al-Qaeda and planning attacks in Europe, with the American embassy in Paris among the targets.

Richard Reid, alleged shoe-bomber and al-Qaeda agent

Mr Beghal attended the Finsbury Park mosque in north London, where many radical young Muslims have been regulars.

He also lived in Leicester, although community leaders in the city have rejected suggestions he recruited fellow extremists at a mosque there.

It is in Leicester that the first charges of al-Qaeda membership in Britain since the US attacks have been brought. Two men are in custody, although proceedings are at an early stage and they have yet to face trial.

Another man arrested in Leicester, Kamel Daoudi, 23, was returned to France after fleeing police wanting to question him - over his involvement in an alleged al-Qaeda cell set up by Mr Beghal.

Extradition

Zacarias Moussaoui is not the only person with links to the UK also suspected by the US of having direct connections with the 11 September attacks.

Algerian pilot Lotfi Raissi is currently being held in Belmarsh high security prison in south London while extradition procedures run their course.

American investigators allege he may have trained four of the hijackers, although British officials reportedly have doubts about their evidence.

It is clear that the breadth of the al-Qaeda network and the number of Muslim militants in the UK is still only just beginning to emerge.

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