FBI agents arrested Paul Kevin Curtis, 42, at 5:15 p.m. Wednesday at his apartment in Corinth, said FBI Special Agent in Charge Daniel McMullen. It wasn’t immediately known where he was being held.
The letters sent to Obama and the Republican senator tested positive for ricin in preliminary tests but were being retested to eliminate the possibility of a false positive. The letters were intercepted before reaching the White House or Senate.
Ricin is a highly toxic substance derived from castor beans. As little as 500 micrograms can kill an adult. There is no specific test for exposure to it, and no antidote once exposed.
An FBI bulletin stated that both letters, postmarked April 8, included the identical phrase: “to see a wrong and not expose it, is to become a silent partner to its continuance.”
Both letters were signed: “I am KC and I approve this message.”