4. SOUNDBITE: (English) Tommy Thompson, US Health and Human Services Secretary
"We learned that the mailbox of the woman who received cutaneous anthrax from New Jersey, her mailbox tested positive. We didn't know that yesterday. The one where she works."
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7. SOUNDBITE: (English) Tommy Thompson, Health and Human Services Secretary
"This science is evolving. We know more today than we did yesterday. Everyday we're learning something regards to the anthrax scare and bioterrorism. We're not only looking at anthrax we're looking at the whole spectrum. In fact I've asked the individuals what's the worst case scenario and how would we respond?"
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9. SOUNDBITE: (English) Tommy Thompson, Health and Human Services Secretary
"Common sense would tell you that it's possible, there's a lot of mail that hasn't been delivered in the last three weeks now, two weeks and FBI and the other individuals are going through these truck loads of mail for the Capitol, and they may be able to find another letter, I don't know, that's pure speculation. But we don't know, there's no proof as of this point in time of more letters but there's a lot of mail that has not been delivered."
10. Close up sign Longworth House Office Building pull out to wide shot and police tape
11. Wide of Tommy Thompson, Health and Human Services Secretary
Investigators have found anthrax in the office mailbox of a New Jersey woman with skin anthrax, indicating she was exposed through the mail like other victims, the US Health Secretary told The Associated Press Friday.
Tommy Thompson said investigators have found traces of anthrax in the mailbox of the 51-year-old accountant in New Jersey, whose case had puzzled them because she had no apparent connection to the mail.
Federal officials also officially confirmed the 17th case of anthrax infection, a New York Post worker who had already been diagnosed by local authorities.
On Capitol Hill, an intense cleanup was under way in the Hart building, where an anthrax-laced letter sent to Senator Tom Daschle was opened.
Workers were sealing doors and windows as they prepared to fill the nine-story building with a killing gas.
Chlorine dioxide is expected to kill everything it touches -- mice, rats, roaches and anthrax spores.
Almost a month into the anthrax mystery, officials said they had little to go on and could not say whether the deadly plot originated at home or abroad.
Three anthrax-laden letters were postmarked from Trenton, New Jersey, that went to Senate Majority Leader Tom Daschle, NBC television and the New York Post.
Spores have turned up in government offices in Washington and media outlets in New York and Florida, as well as mail facilities near Washington, in Florida, New Jersey and the midwestern states of Missouri and Indiana.
In New York, disease specialists searched for clues to explain how a 61-year-old hospital worker, Kathy T. Nguyen, was exposed to anthrax.
Nguyen was too sick to talk before she died Wednesday, and she lived alone with no close family to help retrace her steps.
Investigators know that the bacteria that killed Nguyen were indistinguishable from all the others, including the strain in the letter to Daschle, according to the Centers for Disease Control and Prevention.
Health officials say that could mean anthrax aimed at someone else mixed with other letters in the mail and wound up infecting her.