U.S. officials: Scientist was anthrax killer

Tracking the anthrax
It says that in his lab, Ivins had custody of a flask of anthrax termed "the genetic parent" to the powder involved — a source that investigators say was used to grow spores for the attacks on "at least two separate occasions."

Anthrax culled from the letters was quickly discovered to be the so-called Ames strain of bacteria, but with genetic mutations that made it distinct. Scientists developed more sophisticated tests for four of those mutations, and concluded that all the samples that matched came from a single batch, code-named RMR-1029, stored at Fort Detrick.

Ivins "has been the sole custodian of RMR-1029 since it was first grown in 1997," said one affidavit.

Powder from anthrax-laden letters sent to the New York Post and Tom Brokaw of NBC contained a bacterial contaminant not found in the anthrax-containing envelopes mailed to  Leahy or Daschle, the affidavit said.

Investigators concluded that "the contaminant must have been introduced during the production of the Post and Brokaw spores," the affidavit said.

The documents disclosed that authorities searched Ivins' home on Nov. 2, 2007, taking 22 swabs of vacuum filters and radiators and seizing dozens of items. Among them were video cassettes, family photos, information about guns and a copy of "The Plague" by Albert Camus.

Investigators also reported seizing three cardboard boxes labeled "Paul Kemp ... attorney client privilege."

Ivins' cars and his safe deposit box also were searched.

According to an affidavit filed by Charles B. Wickersham, a postal inspector, the scientist told an unnamed co-worker "that he had `incredible paranoid, delusional thoughts at times' and 'feared that he might not be able to control his behavior.'"

A mental health worker who was involved in treating Ivins disclosed last week that she was so concerned about his behavior that she recently sought a court order to keep him away from her.

Allegations that Ivins sought to mislead investigators ran through the material made public.

A picture of deception
One FBI document said Ivins "repeatedly named other researchers as possible mailers and claimed that the anthrax used in the attacks resembled that of another researcher" at the same facility.

The name of the other researcher was not disclosed.

The documents painted a picture of Ivins seeking to mislead investigators beginning in 2002, when he allegedly submitted the wrong samples to FBI investigators.

It wasn't until more than two years later, in March 2005, that he was confronted with the alleged switch, according to U.S. Postal Inspector Thomas Dellafera, who added that Ivins insisted he had not sought to deceive.

The victims of the attacks had little in common.

Robert Stevens, 63, a photo editor at the Sun, a supermarket tabloid published in Boca Raton, Fla., was the first to die. Thomas Morris Jr. 55, and Joseph Curseen, 47, worked at a Washington-area postal facility that was a hub for sorting the capital's mail. Kathy Nguyen, 61, who had emigrated from Vietnam and lived in the Bronx, worked in a stock room at Manhattan Eye Ear & Throat Hospital. Ottilie Lundgren, 94, who lived in Oxford, Conn., was the last to die.

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