Tupelo, Mississippi (CNN) -- A Mississippi man has been arrested in connection with the investigation into ricin-tainted letters sent to President Barack Obama and other officials, federal and local officials said.
FBI agents arrested James Everett Dutschke of Tupelo at his home early Saturday without incident, said FBI spokeswoman Deborah Madden. Earlier this week, agents searched Dutschke's residence and former martial arts studio, though it's not clear what they found.
On Tuesday, prosecutors dropped charges against another man, Paul Kevin Curtis of Corinth, Mississippi, who was arrested April 17 and accused of sending a threat to the president after letters containing a suspicious powder triggered security scares around Washington.
At a court hearing the day before the charges were dropped, Curtis said he was being framed and identified Dutschke as a potential culprit.
The letters -- sent to Obama; Sen. Roger Wicker, R-Mississippi; and Sadie Holland, a judge in Lee County, Mississippi -- touched off anxieties in Washington and elsewhere in the wake of the bombs at the Boston Marathon. The two incidents were unconnected, officials said.