Anthrax documents point finger at dead researcher

WASHINGTON (CNN) - The suspect in the 2001 anthrax killings tried to mislead federal agents by submitting false samples of the bacteria and used language similar to the letters that were sent to news organizations and leading senators, according to court records released Wednesday.

The Justice Department released hundreds of pages of documents implicating Army biodefense researcher Bruce Ivins. Authorities said Ivins committed suicide last week as federal prosecutors prepared to present the results of the nearly seven-year investigation to a grand jury.

"At the time of the attacks, he was the custodian of a large flask of highly purified anthrax spores that possess certain genetic mutations identical to the anthrax used in the attacks," according to a July 11 affidavit from a U.S. postal inspector.

The affidavit states Ivins "has been unable to give investigators an adequate explanation for his late night laboratory work hours around the time of both anthrax mailings," and submitted false samples to the FBI for analysis.