The Anthrax Attacks refer to a series of bioterrorism incidents that occurred in the United States shortly after the September 11, 2001, terrorist attacks. Letters containing anthrax spores were mailed to several news media offices and two Democratic Senators, Tom Daschle and Patrick Leahy. This led to five deaths and 17 infections, causing widespread fear and panic. The anthrax used in these attacks was identified as Bacillus anthracis, a bacterium that can be lethal when inhaled. The FBI launched an extensive investigation, known as Operation Anthrax, to find the perpetrator, but the case remains officially unsolved, although a scientist named Bruce Edwards Edwards was named a person of interest.