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Events on Tuesday 9 October 2001 1
2001Anthrax letters mailed in the United StatesPowder-filled envelopes kill five peopleBeginning in September 2001, letters containing anthrax spores were mailed to news organisations and two US senators, killing five people and infecting seventeen others. The attacks disrupted mail service and Congress and deepened fears after 9/11. The FBI later concluded that a government biodefence researcher was responsible.