A martial arts instructor from Mississippi has been arrested by US authorities investigating the ricin-laced letters sent to Barack Obama and other officials, police have told Reuters.
Everett Dutschke, 41, was taken into custody this morning from his Tupelo home, which was searched twice last week along with the premises of his former martial arts studio in the city.
US prosecutors dropped charges on Tuesday against another Mississippi man, Elvis impersonator Paul Kevin Curtis.
He was released from jail after a search of his home in nearby Corinth revealed no incriminating evidence.
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