A therapist who counseled an Army scientist under scrutiny for 2001's deadly anthrax attacks recently told a courtroom she was afraid of her patient and described him as "a sociopath, homicidal killer."
The patient, Bruce E. Ivins, a research scientist at the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID) at Fort Detrick, Md., killed himself last week as investigators closed in on indicting him for his alleged role in the post-9/11 anthrax attacks, which killed five and sickened 17.
Counselor Jean Duley had been subpoenaed to testify before a federal grand jury in Washington, D.C., that was considering evidence for an indictment against Ivins. But before her scheduled appearance, she filed a request with a local court in Frederick, Md.
Her account of Ivins' state of mind in the weeks before his death sharply conflicted with the more long-term memories of Ivins' friends, who recalled him as a talented scientist who spent his time outside the lab as a Red Cross volunteer, a musician at his church and a devoted family man.
But in weekly therapy sessions, Duley said she saw Ivins' frightening transformation. And on July 24, she asked the court to protect her from him.
In the audiotaped court appearance, she described her concern about Ivins' behavior at a July 9 group therapy session.
"He was extremely agitated, out of control," Duley said.
"He proceeded to describe to the group a very long and detailed homicidal plan," she said. "Because he about to be indicted on capital murder charges, he was going to go out in a blaze of glory."
Duley went to the police. On July 10, authorities at the Fort Detrick lab where he worked removed him from the premises and had him committed for a psychiatric evaluation. A judge in Frederick, Md., granted an order that required Ivins to cease contact with Duley and stay away from her home and place of work.
The FBI suspects that Ivins' behavior changed after the Justice Department announced a $5.8 million settlement a former scientist from the same Fort Detrick lab. Steven Hatfill, who then-Attorney General John Ashcroft named a person of interest in the case in August 2002, had claimed he was unfairly targeted and his reputation damaged by leaks to the press.
A month later, Ivins, who had been under constant surveillance by the FBI, was dead.
Ft. Detrick was the focus early on in the investigation because it is one of only a few labs known to work with the strain of anthrax used in the attacks.
Investigators narrowed their search further when they produced evidence that envelopes used in the attack were purchased at a post office near Ft. Detrick.
One theory the FBI has been pursuing is whether Ivins might have mailed the anthrax to further his research on anthrax vaccines. His research included classification of anthrax spores and tracking the success of anthrax vaccines administered to animals.
Duley said she feared for her life.
"I'm scared to death," she said on the courtroom audio recording.
And she made this chilling claim: "He has been forensically diagnosed by several top psychiatrists as a sociopath, homicidal killer," she said.
Ivins' lawyer said Friday that his client was innocent, and that he fully cooperated with the government's investigation.
The Justice Department remained tight-lipped on the investigation, releasing a statement Friday saying there have been "significant developments," but declining to elaborate. Next week, the FBI is expected to release its evidence, which is currently under court seal.
ABC News' Z. Byron Wolf contributed to this report.