WASHINGTON Army scientist Bruce Ivins had custody of highly purified anthrax spores with "certain genetic mutations identical" to the poison that killed five and rattled the nation in 2001, according to documents unsealed Wednesday in the government's investigation.
Also, Ivins was unable to give investigators "an adequate explanation for his late laboratory work hours around the time of" the attacks, and he apparently sought to mislead investigators on the case, according to an affidavit filed by one government investigator.
The scientist committed suicide last week as investigators were preparing to charge him with murder in the 2001 attacks. The documents were released as the FBI held a private briefing for families of the victims of the episode, and officials said the agency was preparing to close the case.
The events in Washington unfolded as a memorial service was held for Ivins at Fort Detrick, the secret government installation in Frederick, Md., where he worked. Reporters were barred.
The documents disclose 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.
They also reported seizing three cardboard boxes labeled "Paul Kemp ... attorney client privilege."
Ivins' cars and his safe deposit box also were searched as investigators closed in on the respected government scientist who had been troubled by mental health problems for years.
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.
FBI officials arranged a mid-afternoon news conference to answer questions about the case. They had no immediate comment on the closed-door meeting with families of the victims of the attacks, which lasted more than three hours.
The documents, which were expected to clear up many of the mysteries surrounding the case, were released following an order from U.S. District Judge Royce Lamberth. Among them were more than a dozen search warrants issued as the government closed in on Ivins in an investigation into events that killed five, sickened dozens and rattled the nation a few weeks after the Sept. 11, 2001, terror attacks.
Lamberth ordered the release after consultation with Amy Jeffress, a national security prosecutor at the Department of Justice.
The investigation dates to 2001, when anthrax-laced mail turned up in two Senate offices as well as news media offices and elsewhere. At the time, the events were widely viewed as the work of terrorists, and delivery of mail was crippled when anthrax spores were discovered in mailing equipment that had processed the contaminated envelopes.
The FBI's investigation had dragged on for years, tarnishing the reputation of the agency in the process.
The government recently paid $6 million to settle a lawsuit by Stephen A. Hatfill, whose career as a bioscientist was ruined after then-Attorney General John Ashcroft named him a "person of interest" in the probe.
Ivins' lawyer has maintained that the 62-year-old scientist would have been proved innocent had he lived. And some of Ivins' friends and former co-workers at the Fort Detrick biological warfare lab say they doubt he could or would have unleashed the deadly toxin.
The Justice Department "has a legal and moral obligation to make official statements first to the victims and their families, then the public," Attorney General Michael Mukasey said Tuesday.
Officially, the case will stay open for an undetermined but short period of time. That will allow the government to complete several legal and investigatory matters that need to be wrapped up before it can be closed, the officials said.
The records could shed light on numerous elements of the case. Among the matters still in question:
An advanced DNA analysis matched the anthrax used in the attacks to a specific batch controlled by Ivins. It is unclear, however, how the FBI eliminated as suspects others in the lab who had access to it.
Ivins' purported motive sending the anthrax in a twisted effort to test a cure for it, according to authorities. Ivins complained of the limitations of animal testing and shared in a patent for an anthrax vaccine. No evidence has been revealed so far to bolster that theory.
Why Ivins would have mailed the deadly letters from Princeton, N.J., a seven-hour round trip from his home. In perhaps the strangest explanation to emerge in the case so far, authorities said Ivins had been obsessed with the sorority Kappa Kappa Gamma for more than 30 years. The letters were sent from a mailbox down the street from the sorority's office, which is across the street from Princeton University.
Investigators can't place Ivins in Princeton but say the evidence will show he had disturbing attitudes toward women. Other haunting details about Ivins' mental health have emerged, and his therapist described him as having a history of homicidal and sociopathic thoughts.