Soon after the terrorist attacks of 9/11, letters laced with anthrax began appearing in the US mail. Five Americans were killed and 17 were sickened in what became the worst biological attacks in US history. The ensuing investigation by the Federal Bureau of Investigation (FBI) and its partners—code-named “Amerithrax”—has been one of the largest and most complex in the history of law enforcement.

In August 2008, Department of Justice and FBI officials announced a breakthrough in the case and released documents and information showing that charges were about to be brought against Dr. Bruce Ivins, who took his own life before those charges could be filed.

Ivins was an American microbiologist, vaccinologist, senior bio-defence researcher at the United States Army Medical Research Institute in Fort Detrick, Maryland.