One of the terrorist group's most senior figures warned that al-Qaeda had obtained and hidden a nuclear bomb in Europe that would be detonated if Osama bin Laden was killed or captured.
Khalid Sheikh Mohammed, the al-Qaeda mastermind currently facing trial in America over the 9/11 atrocities, was involved in a range of plans including attacks on US nuclear plants and a "nuclear hellstorm" plot in America.
A number of the conspiracies admitted by detainees during interrogation in Cuba seem improbable, but other plans were detailed and thoroughly analysed.
Some detainees displayed an apparently comprehensive knowledge of Western countries' defences against nuclear attack.
According to the US WikiLeaks files, a Libyan detainee, Abu Al-Libi, "has knowledge of al-Qaeda possibly possessing a nuclear bomb". Al-Libi, the operational chief of al-Qaeda and a close associate of Osama bin Laden before his detention, allegedly knew the location of a nuclear bomb in Europe that would be detonated if bin Laden were killed or captured.
Sharif al-Masri, an Egyptian captured in 2004, allegedly claimed that Al-Libi had said the nuclear bomb's operatives "would be Europeans of Arab or Asian descent". The notes show that US interrogators spent large amounts of time trying to establish whether al-Qaeda had access to nuclear material.
Salman Yehah Kasa Hassan, a Yemeni operative, allegedly said that "an associate of his brother was apprehended attempting to sell uranium for $500,000". However, after the Yemeni authorities confiscated the uranium, "it was rumoured to have disappeared in a transaction with [Osama bin Laden]".
Mohommad Zahir, a "weapons dealer" from Afghanistan, was arrested in 2003 allegedly carrying a memo referring to "two or three cans of uranium", "intended for the production of an 'atom bomb'".
Another detainee "discussed the issue of buried uranium in Kandahar".
Other detainees talked about "a ship purchased by al-Qaeda" which was intended to be used "to transport weapons, explosives, and possibly uranium purchased from countries along the Red Sea and Mediterranean Sea".
Of particular concern to the US was a network of nuclear scientists and military officers called "Ummah Tameer Nau", which was set up "to assist in spreading the modern achievements of science and technology among Muslims".
Al-Qaeda apparently also regularly explored the use of chemicals in attacks, believing that getting these into the US would be easier than nuclear material. The use of biological agents, including anthrax, was also considered. One detainee allegedly claimed that Ammar al-Baluchi, the nephew of Khalid Sheikh Mohammed, discussed "how to smuggle explosives and chemicals into England".
According to the US documents, another key al-Qaeda operative discussed a "dirty bomb" with other plotters, which "would combine a regular explosive with uranium or other radiological material".
The nuclear material "would be disbursed throughout a limited region due to the blast, exposing all within the area to the radiated material". The terrorists' aim was to cause "latent illness for most, as well as widespread panic far exceeding the affected area".
