Investigators say the same type of anthrax spore seen in the first case discovered at the offices of American Media, Inc., in Florida was also in the letter sent to NBC anchor Tom Brokaw and the one sent to Senator Tom Daschle.
The spate of anthrax infections could be an organized conspiracy, Attorney General John Ashcroft says. Anthrax fears are prompting changes in corporate mailrooms all over the country. Workers are being given latex gloves, surgical masks, and protective glasses.
"It appears as if there are some similarities between some of the most serious of the offenses that indicate that they might be . . . a part of a unified organized effort, an effort either by a single individual or else an effort conducted in concert with someone else," Ashcroft says.
Tests are still being conducted on the type of spore used in other cases, say officials. Upon further examination, the spores don't look to be as high grade as first thought.
"It looked to be run-of-the-mill. They're sensitive to all antibiotics," says Dr. Bill Winkenwarter of the Defense Department.
The strain's sensitivity is a sign that the spores may not have been designed for use in military weapons, since most military-grade anthrax is treated to resist antibiotics like penicillin and Cipro.
Thus far, the FBI has responded to 2,500 suspected anthrax threats across the country but has actually found the bacteria in only three locations: Boca Raton, Florida, Washington, DC, and the New York area. And although 4,000 people have been tested, just 35 were found to be exposed but disease-free. Only seven others were actually infected, one of whom died.
Meanwhile, the FBI and Postal Service announced a $1 million reward for whoever mailed the letters.
FBI Director Robert Mueller says the reward would be for "information leading to the arrest and conviction for terrorist acts of mailing anthrax."
Sources say investigators believe the letters were mailed from one or two post offices in the Trenton, New Jersey, area and are fanning out to all the street mailboxes nearby.
On the assumption that the suspect may have dosed himself preventively with antibiotics, they're also checking pharmacies in the area for purchases in mid-September.
Although they have no definite evidence one way or the other, investigators still haven't ruled out a domestic criminal, perhaps acting alone.
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