U.S. & World

WASHINGTON (AP) ― The suspect suddenly emerged seven years after anthrax-laced letters terrorized a jittery country, then was gone just as quickly, committing suicide before authorities could charge him with murder.

The government's working theory is that brilliant but troubled Army scientist Bruce E. Ivins released the anthrax to test his cure for the toxin. That may answer some questions, but many details remain unclear.

"I think the FBI owes us a complete accounting of their investigation and ought to be able to tell us at some point, how we're going to bring this to closure," said former Senate Democratic leader Tom Daschle of South Dakota, whose office received a letter containing the deadly white powder in 2001. "I think the American people deserve to know more than they do today."

Ivins' emergence as the top -- and perhaps only -- suspect came soon after the government exonerated another Army scientist in the case. Last month, the Justice Department cleared Ivins' colleague, Steven Hatfill, who had been wrongly suspected in the case, and paid him $5.8 million.

Responding to reports about Ivins on Friday, the department said only that "substantial progress has been made in the investigation" and that it soon may be able to release more information about the case.

The department is expected to decide within days whether to close the "Amerithrax" investigation now that its main target is dead. If the case is closed, authorities are expected to speak with the families of the victims and update them about their case against Ivins.

Among the biggest unanswered questions is what led the FBI to Ivins after all these years. Ivins attracted some attention for conducting unauthorized anthrax testing in the six months following the anthrax mailings, but the FBI focus stayed on Hatfill.

The department attributed the progress to "new and sophisticated scientific tools."

Investigators said the science focused, in part, on how the anthrax strains were handled and who had access to it at the time of the mailings. Had the same process been used years ago, it would have cleared Hatfill, according to two people familiar with the FBI investigation who spoke on condition of anonymity because the case is not officially closed.

Documents related to the investigation remain sealed.

For 35 years, Ivins was one of the government's leading scientists researching vaccines and cures for anthrax exposure, work that earned him the Pentagon's highest honor for civilian employees.

His research included one study that complained about the limits of testing anthrax drugs on animals. Eighteen months before the anthrax letters were sent, Ivins and other scientists applied for a patent for their anthrax vaccine.

The letters containing anthrax powder were sent soon after the attacks of Sept. 11, 2001. The letters turned up at congressional offices, newsrooms and elsewhere, leaving a deadly trail through post offices on the way. The powder killed five and sent numerous victims to hospitals and caused near panic in many places.

Ivins' friends, colleagues and court documents paint a picture of a flourishing scientist with an emotionally unstable side. Maryland court documents show he recently received psychiatric treatment and was ordered to stay away from a woman he was accused of stalking and threatening to kill.

Social worker Jean C. Duley filed handwritten court documents last week saying she was preparing to testify before a grand jury. She said Ivins would be charged with five capital murders.

"Client has a history dating to his graduate days of homicidal threats, plans and actions towards therapists," Duley said, adding that his psychiatrist had described him as homicidal and sociopathic.

Several U.S. officials said prosecutors had been focusing on the 62-year-old Ivins and planned to seek an indictment and the death penalty. There was talk of a plea deal that would have instead sent Ivins to prison for life. Ivins' lawyer was open to discuss the deal but his client killed himself before an agreement could be reached, one official said.

The officials all discussed the continuing investigation on condition of anonymity because they were not authorized to speak to the media.

Ivins' lawyer, Paul F. Kemp, asserted the scientist's innocence and said he had cooperated with investigators for more than a year.

"We are saddened by his death, and disappointed that we will not have the opportunity to defend his good name and reputation in a court of law," Kemp said.

Ivins died Tuesday at Frederick Memorial Hospital in Maryland. Relatives told The Associated Press that he killed himself. Kemp said his client's death was the result of the government's "relentless pressure of accusation and innuendo."

Rescue crews had responded to Ivins' home shortly after 1 a.m. last Sunday for a report of an unconscious man and took him by ambulance to the hospital, according to police and fire officials.

The Fort Detrick laboratory and its specialized scientists for years have been at the center of the FBI's investigation of the anthrax mailings. In late June, the government exonerated Hatfill, whose name has for years had been associated with the attacks. Then-Attorney General John Ashcroft called him a "person of interest" in 2002.

Authorities recently reached out to Hatfill to let him know something was about to break in the case, but they didn't ask for his cooperation because there was nothing for him to help with, one of the people close to the case confirmed.

Authorities had watched Ivins for some time. His brother, Tom Ivins, said federal agents questioned the scientist about a year and a half ago. Neighbors said FBI agents in cars with tinted windows conducted surveillance on his home. A colleague, Henry S. Heine, said that over the past year, he and others on their team had testified before a federal grand jury in Washington that has been investigating the anthrax mailings.

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