9/11 Anthrax investigation quietly loses urgency

September 28, 2005 In the past year, the FBI has sharply reduced the number of staff investiging the post-9/11 Anthrax probe attack from 31 to 21; and the post office has reduced the number of investigators from 13 to 9. The investigation has been one of the most extensive in FBI history but has yielded no arrests. The reward for information leading to an arrest and conviction remains at $2.5 million. The FBI is preparing an internal report to take stock of the situation, as is usually done in high-profile cases which go unresolved for years, and are expected to remain so. The magnitude of the Anthrax probe parallels the 18-year Unabomber probe, which was only resolved because Theodore Kaczynski issued a public manifesto and his brother recognized his thinking and tipped off the FBI.

The prevailing theory in the Anthrax probe is that "the culprit is a U.S. scientist who had access to the high-grade anthrax and the knowledge of how to physically manipulate it and use it as a weapon", a theory which emerged early in the investigation. The attacks used a weaponized Ames strain almost surely produced in the U.S., most likely at Fort Detrick.

The purpose of the attack also remains unknown but many believe it was committed by conservative elements in American society, due to the existence of coordinated harmless attack, the choice of targets, and the choice of strain. Some believe the attack was aided by Lt. Col. Dr. Philip Zack, perhaps with the intent to frame ex-coworker Dr. Ayaad Assaad whom Dr. Zack harassed while at Fort Detrick.

The post-9/11 Anthrax attacks killed 5 people and temporarily infected another 17.