The suspect, Paul Kevin Curtis, 45, was arrested by FBI on Wednesday at his residence in Corinth, responsible for the mailings of the three letters sent through the US Postal Service which contained a granular substance that preliminarily tested positive for ricin.
The letters were addressed to US President, Senator Roger Wicker and a Mississippi justice official.
The individual was arrested following an investigation conducted by FBI Joint Terrorism Task Forces in Memphis, Tennessee and Jackson, Mississippi, the US Capitol Police, and other federal and local agencies.
The FBI has said that there is no connection between blasts at the Boston marathon that took three lives and mailings sent to US President and other leaders.
According to a local television network, the letter said the person who wrote it said that they tried to talk to someone and that no one would listen and now someone must die.
The letter was reportedly signed with the same signature as the two letters sent to Obama and Wicker.
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