Anthrax investigation

In the fall of 2001, just weeks after the 9/11 attacks, five people were killed and 22 more sickened by anthrax, sent in anonymous letters to media and government organizations.

The FBI created a profile of the suspect as a male loner and bioweapons expert Steven Hatfill was wrongly identified as a person of interest, generating a multimillion-dollar lawsuit.

Another researcher, Bruce Ivins, killed himself in July 2008 after learning of a possible prosecution. Now, the FBI says it has solved the case.