FBI director Robert Mueller acknowledges that investigators might have been able to uncover part of the plot that led to the terror attacks of 11 September. This is believed to be the first time a US official has admitted this. Mr Mueller said if all the clues had been put together, "who is to say" what could have been discovered.
FBI guidelines give agents more latitude to monitor e-mails, internet sites, libraries and religious institutions without first having evidence of criminal activity. A spokesperson for the American Civil Liberties Union says: "The FBI is telling the American people that they no longer have to do anything unlawful to get that knock on the door."