Federal investigators today refocused their hunt for criminal evidence in the anthrax mystery at an office in Florida. CBS's Bobbi Harley reports they did so as a third office worker there tested positive for anthrax bacteria.
Federal investigators shifted gears today. Instead of finishing--as planned--the examination of the building where anthrax was found, they moved back in with renewed interest--focusing on how the bacteria got into the offices of tabloid newspaper publisher American Media.
US officials are operating on the theory it came in through the mailroom, which is located on the first floor of the Boca Raton building just off the main lobby.
That's where 73-year-old Ernesto Blanco worked: He tested positive for exposure to anthrax. But it was Robert Stevens who contracted the disease and died. And so far, Stevens's computer keyboard is only place where anthrax spores have been discovered.
Police have blocked off the Boynton Beach home of the third co-worker who was exposed to the bacteria while they determine how the 35-year-old woman interacted with the two other victims.
Still, the best evidence the FBI has to date is the anthrax itself.
"It's now a pistol for which we know the marks it puts on the bullet. And if it turns up anywhere else it'll be immediately recognizable as being unique," says Dr. Martin Hugh-Jones.
Hugh-Jones is a leading global expert on anthrax and is sharing information from the FBI with other laboratories, trying to match the so-called genetic fingerprint of the Florida sample to known anthrax strains worldwide.
Scientists at Los Alamos National Lab, where some of the work is being done, call it a monumental job.
Jill Trewhella, biosciences manager at Los Alamos National Lab, says, "We have more than 1,200 [strains] in our database. How many there are in the globe I'm not sure."
The clues investigators are looking for in this building are microscopic--anthrax spores authorities are now assuming were planted here on purpose.
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