"It says, in essence, you've been exposed to anthrax, have a nice life," says Tom Kubic of the FBI.
FBI officials in Washington say there is nothing "nice" about these anthrax hoaxes because they are costing investigators time and money. More than 60 of them have been sent since January, most of them targeting abortion clinics. So far none has been real.
Neil Gallagher, FBI assistant director, says "My personal fear is that they'll be someday a real anthrax threat, and the American society will react by saying there's another hoax threat and we shouldn't take it seriously."
The FBI is so serious about hunting down the letter senders that it has issued this warning: You could go to prison for life for even threatening to use biological weapons, including anthrax.
Last month, Los Angeles staged the largest dress rehearsal yet for a disaster caused by anthrax and other germ warfare. Unlike a bomb, rescuers and victims won't be able to see the agents that are killing them.
Steve Ruda of the L.A. Fire Department warns "It is odorless, it is colorless. The victims don't know what has happened to them."
As one law enforcement official told CBS News, almost nostalgically, "we'd rather have an old-fashioned bomb threat than the hoaxes we're chasing now."
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