An anonymous source involved with the case revealed Friday that the FBI will close their investigation on the 2001 anthrax case.
The act of bioterrorism began just days after the September 11th attacks, when letters laced with anthrax were sent with childish, blocky handwriting and chilling scientific expertise to various news media outlets and politicians, including Tom Brokaw of NBC News and South Dakota Senator Tom Daschle.
The case was one of the most vexing and costly investigations in U.S. history until officials announced in 2008 that they were beginning to focus on Dr. Bruce Ivins, a scientist who worked at a government biodefense lab in Maryland, as their main suspect.
Ivins later killed himself as authorities prepared to indict him. The move Friday seals that preliminary investigative conclusion, citing him as the sole culprit.
The anthrax spores killed five people: Two postal workers in Washington, a New York City hospital worker, a Florida photo editor and a 94-year-old Connecticut woman who had no known contact with any of the poisoned letters. Seventeen other people were sickened.