Thousands of Islamist militants in the UK are actively supporting jihadist activities at home and abroad, according to a leaked Government document.
The secret report states that Britain will remain "a high-priority target" for international terrorists aligned with al Qaida for the foreseeable future.
And it warns that a network of extremist cells exists in the UK, with the main concentrations in London, Birmingham and Luton.
The document - marked "restricted" - was reportedly drawn up by the intelligence branch of the Ministry of Defence, MI5 and Special Branch.
The threat from Islamist extremists is "diverse and widely distributed" and the number of terrorists in Britain is "difficult to judge", states the report.
But it cites estimates from the Joint Terrorism Analysis Centre that there are "some thousands of extremists in the UK committed to supporting jihadi activities, either in the UK or abroad".
And it states: "For the foreseeable future the UK will continue to be a high-priority target for international terrorists aligned with al Qaida.
"It will face a threat from British nationals, including Muslim converts, and UK-based foreign terrorists, as well as terrorists planning attacks from abroad."
In 2006, the then head of the Security Service, Dame Eliza Manningham-Buller said that MI5 was aware of 30 major terrorist plots and had 1,600 people in 200 cells under surveillance. Last year, her successor Jonathan Evans said the number had grown to 2,000.
A Home Office spokesman said: "We do not comment on leaked documents."
The secret report states that Britain will remain "a high-priority target" for international terrorists aligned with al Qaida for the foreseeable future.
And it warns that a network of extremist cells exists in the UK, with the main concentrations in London, Birmingham and Luton.
The document - marked "restricted" - was reportedly drawn up by the intelligence branch of the Ministry of Defence, MI5 and Special Branch.
The threat from Islamist extremists is "diverse and widely distributed" and the number of terrorists in Britain is "difficult to judge", states the report.
But it cites estimates from the Joint Terrorism Analysis Centre that there are "some thousands of extremists in the UK committed to supporting jihadi activities, either in the UK or abroad".
And it states: "For the foreseeable future the UK will continue to be a high-priority target for international terrorists aligned with al Qaida.
"It will face a threat from British nationals, including Muslim converts, and UK-based foreign terrorists, as well as terrorists planning attacks from abroad."
In 2006, the then head of the Security Service, Dame Eliza Manningham-Buller said that MI5 was aware of 30 major terrorist plots and had 1,600 people in 200 cells under surveillance. Last year, her successor Jonathan Evans said the number had grown to 2,000.
A Home Office spokesman said: "We do not comment on leaked documents."
Source: ITN
H/T: Jihad Watch