The FBI announced Thursday its agents are looking for a letter , this one directed to the Central Intelligence Agency , that it believes was similar to at least three other letters that contained ricin . The FBI says four similar letters were postmarked the same day , with similar contents . Tests show three of those letters had ricin ; tests are pending on the fourth one . The FBI is looking for a letter that was sent to the CIA . All five letters are believed to have been sent from Spokane around May 13 .
The FBI says four similar letters were postmarked the same day , with similar contents . Tests show three of those letters had ricin ; tests are pending on the fourth one . The FBI is looking for a letter that was sent to the CIA . All five letters are believed to have been sent from Spokane around May 13 .