A man has been accused of threatening US President Barack Obama and others after he allegedly posted them letters containing suspected ricin. Paul Kevin Curtis, 45, is scheduled to appear in federal court later and if convicted could face up to 15 years in prison
He is reported to have believed he had uncovered a conspiracy to sell human body parts on the black market and claimed "various parties within the government" were trying to ruin his reputation.
An affidavit says the letters sent to Mr Obama, US Senator Roger Wicker and a judge in Mississippi told the recipients: "Maybe I have your attention now even if that means someone must die."
Curtis was arrested at his home in Corinth, Mississippi. He had been living in Corinth, a city of about 14,000, since December, but local police had not had any contact with him before his arrest, Corinth Police Department Capt Ralph Dance said. He said the department aided the FBI during the arrest and that Curtis did not resist being taken into custody. Police maintained a cordon around Curtis' home, and federal investigators were expected to search the house later in the morning, said local officers on the scene.
Four men who appeared to be investigators were in the neighbourhood to speak to neighbours. There didn't appear to be any hazardous-material crews, and no neighbours were evacuated.
The material discovered in a letter to Mr Wicker has been confirmed through field testing and laboratory testing to contain ricin, said Senate Sergeant-at-Arms Terrance Gainer. The FBI has not yet reported the results of its own testing of materials sent to Mr Wicker and Mr Obama.
"Our field tests indicate it was ricin. Our lab tests confirm it was ricin. So I don't get why others are continuing to use equivocal words about this," Mr Gainer said.
An FBI intelligence bulletin said the two letters were postmarked Memphis, Tennessee. Both letters said: "To see a wrong and not expose it, is to become a silent partner to its continuance." Both were signed, "I am KC and I approve this message."
Curtis' neighbours, who said he did not seem violent, were concerned about their safety and worried by the idea that someone was making poison in a house that sits so close to their bedrooms and front yards. A church, and a community centre with an outdoor children's play area, are just steps from Curtis' house.
Ricky Curtis, who said he was Kevin Curtis' cousin, said the family was shocked by the news of the arrest. He described his cousin as a "super entertainer" who impersonated Elvis and numerous other singers. "We're all in shock. I don't think anybody had a clue that this kind of stuff was weighing on his mind," Ricky Curtis said.