excerpt from http://www.nytimes.com/2001/12/03/national/03POWD.html The preliminary analysis of the powder shows that it has the same extraordinarily high concentration of deadly spores as the anthrax produced in the American weapons program. While it is still possible that the anthrax could have a foreign source, the concentration is higher than any stock publicly known to be produced by other governments. The similarity to the levels achieved by the United States military lends support to the idea that someone with ties to the old program may be behind the attacks that have killed five people. The Federal Bureau of Investigation recently expanded its investigation of anthrax suspects to include government and contractor laboratories as a possible source of the deadly powder itself, or of knowledge of how to make it.