James Everett Dutschke, 42, of Tupelo, waived a Wednesday hearing and pleaded not guilty in paperwork his attorney submitted to the U. S. District Court in Oxford, WTVA-TV, Tupelo, reported Tuesday.
Dutschke was arrested in April after a federal grand jury indicted him. He was re-indicted Nov. 21 on additional charges after being accused of trying to have a biological weapon made from his jail cell, the TV station said.
Dutschke has been held without bond on charges of producing and stockpiling a biological weapon, threatening the president, mailing threatening communications and concealing the fact he sent the letters.
Authorities allege Dutschke tried in June to have other people acquire the ingredients, tools and implements to make the toxin ricin, and then put it into an envelope to be mailed to U.S. Sen. Roger Wicker, R-Miss.
Initially, he was charged with mailing letters tainted with ricin to President Barack Obama and Lee County Circuit Court Judge Sadie Holland, as well as Wicker.