Eight of the eleven have been charged with offences of conspiracy to murder and a new offence of preparing acts of terrorism. The other three, including the mother of an eight-month-old baby, have been charged with offences under the Terrorism Act 2000.

All eleven will appear today at City of Westminster Magistrates’ Court. They were arrested on August 10 in connection with an alleged plot to commit murder by bringing down transatlantic passenger jets.

Deputy Assistant Commissioner Peter Clarke, of the Metropolitan Police, said yesterday that officers had uncovered bomb-making chemicals and electrical components. “First there is evidence from surveillance carried out before August 10. This includes important, indeed highly significant, video and audio recordings. Since August 10 we have found bomb-making equipment. There are chemicals, including hydrogen peroxide, electrical components, documents and other items,” he said.

Videos of suspected terrorists meant for broadcast after they had carried out suicide bombings had also been found, he said. “ These are sometimes referred to as martyrdom videos,” he said.

Eleven other suspects remain in custody. One woman has been released without charge.

Unusually, Mr Clarke went into significant detail about the evidence uncovered by police inquiries. “There have been 69 searches. These have been in houses, flats and business premises, vehicles and open spaces,” he said. Searches had also found more than 400 computers, 200 mobile telephones and 8,000 computer media items such as memory sticks, CDs and DVDs, he said.

“The scale is immense. Inquiries will span the globe. The enormity of the alleged plot will be matched only by our determination to follow every lead,” he said.

Susan Hemming, head of the Crown Prosecution Service counter-terrorism division, said that the decision to press charges was taken after “carefully examining and assessing the evidence against each individual with the assistance of anti-terrorist officers in order to come to charging decisions at the earliest practicable opportunity”.

Security sources said that police were still continuing investigations in relation to eight of the remaining suspects. If they are not formally charged by tomorrow, their solicitors can apply for their release.

Saghir Hussein, a solicitor for Cossar Ali, discovered that his client had been charged yesterday as he appeared at court to challenge her detention. She was seeking a High Court order requiring disclosure of the reasons for the decision to extend custody.

There was some surprise in legal circles at the details of evidence given by police, albeit in broad terms, after their own strictures to the media to be careful about the dangers of contempt of court in reporting.

The charges

The following are charged with conspiracy to murder and smuggling explosive devices on to aircraft to detonate them there:

Ahmed Abdullah Ali, aka Abdullah Ali Ahmed Khan, 25, London E17;
Tanvir Hussain, 25, London E10;
Umar Islam (born Brian Young), 28, High Wycombe, Buckinghamshire;
Waheed Arafat Khan, 25, London E17;
Assad Ali Sarwar, 26, High Wycombe;
Osman Adam Khatib, 19, London E17;
Ibrahim Savant, 25, London E17;
Waheed Zaman, 22, London E17.

The following face other, related charges:

Cossor Ali, 23, London E17;
Mehran Hussain, 23, London E10;
a 17-year-old male

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