Anti-terrorist officers are questioning four people arrested in Britain in connection with the attacks on New York's World Trade Centre. The three men and one woman were held after a request from the FBI.
None of the suspects are thought to be directly involved in the attacks but could have provided planning or support.
The three men and a woman are "not run-of-the-mill" suspects, said a security source. The fact they are being held under anti-terrorism legislation is seen as significant.Two men, aged 27 and 29, and a woman, 25, were seized during raids on two homes in west London yesterday morning.
A fourth man, in his 40s, was arrested later in the day after being located in Birmingham.
It is the second time Scotland Yard's anti-terrorist officers have carried out an operation on behalf of the FBI. Last Saturday, they raided a house in Brixton, south London, in search of a woman in her 30s who is linked to a suspect being held in the United States. The woman was not apprehended.
She was named by Zacarias Moussaoui, who had lived in Brixton until February this year and was arrested last month by the FBI in Minnesota after raising suspicions among staff at a flying school.
The FBI is said to believe five of the hijackers prepared for the attacks in Britain. It has requested all their contacts in the UK are questioned.
Officers had search warrants, issued under the Terrorism Act 2000 for the properties raided yesterday and are believed to have removed bundles of documents.
Suspects arrested under the Terrorism Act can be held for a maximum of seven days without charge. An extension of up to five days can be granted by magistrates after the initial 48 hours.
A further British connection has been revealed after seven people were arrested in Paris yesterday in connection with a suspected plot to attack American targets in France.
The seven are said to be linked to Djamel Begal, a French Algerian seized in Dubai in July, who told of plans to blow up the US embassy in Paris.
Relatives of two arrested brothers, Jerome and David Courtellier, claim the pair had been recruited to a terrorist cell while they were living in Brixton with Mr Moussaoui.Reuse content