The files, handed to The Guardian and Daily Telegraph by WikiLeaks, also indicate at least 35 terrorists held at Guantanamo had been radicalised by extremist preachers in the UK.
Abu Qatada and Abu Hamza are identified in the documents as having recruited and sent dozens of extremists from all over the world to fight against the West in Pakistan and Afghanistan.
It also appears the US government suspected the BBC of being a "possible propaganda media network" for al Qaeda after a phone number for the World Service was found in the possession of several suspected terrorists.
But a spokeswoman for the corporation said: "Independence and impartiality are at the heart of all BBC World Service output.
"The service has interviewed representatives of organisations from all sides involved in the Afghan conflict so it would not be surprising that a number believed to relate to the BBC Pashto service was in circulation."