SEATTLE (AP) - The FBI is confirming that the lethal poison ricin was on a letter sent to Fairchild Air Force Base in Washington state earlier this month.
Authorities had said Thursday that three ricin-tainted, hand-addressed letters postmarked May 13 in Spokane were mailed to President Barack Obama, a federal judge in Spokane and a post office in that city.
The FBI had said a fourth letter that was also postmarked May 13 in Spokane and sent to the nearby Air Force base was being analyzed. Agency spokeswoman Ayn Dietrich said Friday that testing shows there was ricin on that mailing.
A 37-year-old man accused of sending one of the letters, containing ricin and a death threat to U.S. District Judge Fred Van Sickle, was arrested May 22. Matthew Ryan Buquet was charged last week with one count of mailing a threatening communication. He pleaded not guilty and is being held without bail in Spokane.
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