However, it does not look likely that the latest anthrax sample, sent to a newspaper in Karachi, can have come from the source recently posited by the FBI - a right-wing US militant.
Note how these Observer reporters still believe that the letter sent to the Jang in Pakistan contained genuine anthrax. In saying what they do, they are probably reflecting what they have been told by British defense officials. I strongly suspect our government was lying when it said the Pakistani letters tested negative for anthrax.
The Observer is the Sunday version of the left-wing Guardian. For this hawkish stuff to appear there is highly significant.