US investigators unable to link 'shoe bomber' to bin Laden

Despite five months of intensive investigation and an apparent welter of circumstantial evidence, American authorities are still unable to say for certain that Richard Reid acted on behalf of al-Qa'ida when he allegedly attempted to blow up an American Airlines flight in December with explosives concealed in his shoes.

According to the latest court filing in the case, the prosecution believes that Mr Reid "was not unassisted", and that the discovery of a palm print and a human hair in one of the shoe bombs, neither matching the defendant, points to the existence of at least one "confederate".

However, federal prosecutors have been unable to name anyone else involved in the plot to blow up Flight 63 from Paris to Miami, and although they have alleged that Mr Reid was trained at an al-Qa'ida camp in Afghanistan, they have not been able to state firmly that he was acting for Osama bin Laden's organisation.

The lack of a firm link seems surprising, especially since the recovery of thousands of files from an al-Qa'ida computer that fell into the hands of two Wall Street Journal reporters in late December, shortly after Mr Reid's arrest. The files referred to an al-Qa'ida operative named as Abdul Ra'uff, travelling under a British passport, whose movements last summer matched Mr Reid's exactly – starting in Belgium, then going on to Israel, Egypt, Turkey and Pakistan before returning to Europe. The operative, the files said, was seeking suitable targets. The fact that Mr Reid has not been named as Abdul Ra'uff suggests the authorities are still unsure of the link.

According to law enforcement officials quoted in yesterday's Los Angeles Times, they believe Mr Reid may have been working with other radical Muslim groups, such as Hamas or Hizbollah.

Mr Reid, 28, a British citizen of Jamaican origin, is in custody in Boston, where the plane landed. He faces nine counts of attempted mass murder.

Among the pieces of evidence identifying him as a suicide bomber is an e-mail to his mother, cited in the latest court filing, which he wrote two days before his arrest. Calling his e-mail his "will", he wrote: "I didn't do this act out of ignorance nor did I do [it] just because I want to die, but rather because I see it as a duty upon me to help remove the oppressive American forces from the Muslim land and that this is the only way for us to do so as we don't have other means to fight them."