It's murder by mail and an effort to spread fear. The FBI still has no firm evidence as to who's behind it.
The latest cases do not appear to represent new attacks, reports CBS News correspondent Jim Stewart, but rather more infections from the same letters. In New Jersey, where all the known letters were mailed from, there's another tentative diagnosis of a postal worker. At the State Department, a worker in a remote mail facility has been diagnosed with anthrax.
Meanwhile, officials say they still don't know who made it, who mailed it, or where it came from. But they're certain it's all connected.
"I can say to you without question this is anthrax and the samples from New York, Washington, and Florida are all from the same family or strain," says Major General John Parker, the commanding general of the US Army Medical Research and Material Command.
But while they're from the same strain, officials confirmed, the anthrax in the letter to Senator Tom Daschle was described as "fine and floaty," meaning more likely to be inhaled, while the bacteria sent the New York Post was described as "coarse."
"One of my scientists actually described the New York Post sample as looking like Purina Dog Chow--you know, clumpy like a pellet," said General Parker.
All of which leaves investigators pretty much where they have been: still believing there is no connection to organized terrorism but not ruling it out, no evidence that another nation like Iraq sponsored the letters, but not ruling that out either, and still canvassing US laboratories and medical facilities for any missing anthrax.
Meanwhile the Postal Service says it's examining 200 mail facilities up and down the eastern seaboard for signs of anthrax. Postal employees lined up for nasal swabs, and in the Senate, lawmakers passed a bill making it easier for police to track and detain suspected terrorists of all types. The president is expected to sign it into law tomorrow.
Federal agents say what they need is a break: someone who's seen something suspicious, maybe the discovery of another letter, or even better, catching someone trying to put one in the mail.
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