Affidavit: Dust mask tied to suspect tests positive for ricin April 30, 2013 -- Updated 2147 GMT (0547 HKT) Affidavit: Dust mask and other samples tied to a Mississippi man positive for ricin Another man had been arrested, accused of sending letters with ricin to Obama, others That man pointed authorities to James Everett Dutschke, 41 A witness says Dutschke talked about being able to make a "poison" and mail it to officials (CNN) -- A dust mask linked to 41-year-old Mississippi resident James Everett Dutschke, among other samples, tested positive for ricin, according to an affidavit unsealed Tuesday. Federal authorities arrested Dutschke on Saturday on charges of possessing and using ricin in connection with letters sent to, among others, President Barack Obama. Dutschke was taken into custody after authorities initially charged -- and then cleared -- Paul Kevin Curtis, another Mississippi man with whom he has sometimes feuded. After his April 17 arrest, Curtis brought up Dutschke as someone who may be responsible for mailing letters with suspicious substances to Obama, Sen. Roger Wicker, R-Mississippi, and Sadie Holland, a judge in Lee County, Mississippi, according to the affidavit in support of a criminal complaint filed in the U.S. District Court for northern Mississippi. A witness told law enforcement agents on April 19 that Dutschke years ago said he could make a "poison," the affidavit said. "Dutschke stated that he could place the poison in envelopes and send them to elected officials," the witness stated, according to the affidavit. ..." According to the witness ... Dutschke made reference to having 'a secret knowledge' for 'getting rid of people in office.' On April 22, federal authorities searched a trash receptacle from Dutschke's Tupelo home and found, among other items, different types of yellow paper, address labels and a dust mask. The letters to Obama, Wicker and Holland were all on yellow paper. That same day, FBI agents spotted Dutschke leaving his former taekwondo facility, loading things into his car, then placing several items from his window into a public trash receptacle. According to the affidavit, these items included a coffee grinder, a box with latex gloves, a dust mask and an empty bucket of floor adhesive. Three subsequent tests by the National Bioforensic Analysis Center of the mask came back positive for ricin, the document states. Authorities further searched Dutschke's former taekwondo dojo and tested six other samples, including liquid removed a drain and swabs taken from inside the building. Five of those samples tested positive for ricin, according to the affidavit. Wearing an orange jumpsuit, and his hands and feet shackled as he entered a federal courtroom Monday, Dutschke told Magistrate S. Allan Alexander that he understood what he had been charged with. His attorney, George Lucas, told Alexander that they had not yet had time to go through the complaint. A preliminary hearing in Dutschke's case is set for Thursday.