FBI Narrowing Focus on Four Suspects in 9/11 Anthrax Attacks

Among the pool of suspects are three scientists — a former deputy commander, a leading anthrax scientist and a microbiologist — linked to the research facility, known as USAMRIID.

The FBI has collected writing samples from the three scientists in an effort to match them to the writer of anthrax-laced letters that were mailed to two U.S. senators and at least two news outlets in the fall of 2001, a law enforcement source confirmed.

The anthrax attacks began shortly after the Sept. 11, 2001, terror attacks, further alarming a nation already reeling from the deaths of 3,000 Americans. Five people were killed and more than a dozen others were infected by the deadly spores in the fall of 2001.

A leading theory is that the anthrax was stolen from Fort Detrick and then sealed inside the letters. A law enforcement source said the FBI is essentially engaged in a process of elimination.

Much of the early public focus fell on a Fort Detrick scientist named Steven Hatfill, who is suing federal authorities for identifying him as a person of interest. Now the FBI is focusing on other scientists at the facility.