An arrest has been made in Mississippi over the suspicious letters which tested positive for the toxin ricin.
FOX News Radio's Rich Johnson reports from Washginton:
The two charges that Paul Kevin Curtis now faces are about making threats through the mail. They are not about ricin, the poison that a government source tells FOX News was, indeed, in the letters sent to President Obama, Senator Roger Wicker and a judge in Mississippi.
The charging papers say that Curtis has sent several letters to Wicker's office, often talking about his belief that someone's selling body parts on the black market.
Curtis' attorney says his client was surprised when he was arrested on Wednesday and that Curtis is innocent.
In Washington, Rich Washington, FOX News Radio.
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