A martial arts instructor was arrested by federal agents Saturday in connection with the investigation into letters containing ricin sent to President Obama, Sen. Roger Wicker (R-Miss.) and a local official, according to reports.

Everett Dutschke was arrested by U.S. marshals at his home in Tupelo, Miss., the city’s police chief said, according to Reuters.

It was not clear yet if Dutschke had been charged. FBI agents had searched his home and business earlier this week.

The arrest comes less than a week after the man authorities initially accused of sending the ricin letters, Paul Kevin Curtis, was released, and the charges against him were dismissed.