Peter Eisler, Kevin Johnson and Aamer Madhani, USA TODAY
The Mississippi man accused of mailing letters with suspected ricin has been charged with threatening President Obama and others.
The U.S. Department of Justice said in a news release Thursday that Paul Kevin Curtis, 45, faced two federal charges accusing him of threatening the president and others.
Curtis was to appear in federal court Thursday. If convicted, he could face up to 15 years in prison.
An affidavit says the letters sent to Obama, U.S. Sen. Roger Wicker, R-Miss., and a judge in Mississippi told the recipients: "Maybe I have your attention now even if that means someone must die."
Laboratory tests have confirmed that the poison ricin was present in a letter sent to Wicker, a federal law enforcement official said Thursday. It was not immediately clear, however, what level of the poison was present in the letter and in a similar letter sent to Obama, which also tested positive for ricin in a preliminary analysis.
The official, who is not authorized to comment publicly, said there were no reports that anyone had been sickened by the letters, which were intercepted by authorities before they were delivered.
Wicker said he had met Curtis. "I have indeed met the gentleman, yes. At a social event," he told reporters outside the Senate chamber after voting on amendments to the gun bill.
"He's an entertainer. He's an Elvis impersonator," Wicker said.
Wicker said the man performed at a party he and his wife gave for a young couple about to get married a decade ago.
"It's my understanding that since that time he's had mental issues, and may not be as stable as he had been," he said.
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Details were beginning to emerge Thursday onCurtis, who was arrested Wednesday at his home in Corinth, Miss.
Multiple online posts on various websites under the name Kevin Curtis appear to show a man who 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. The posts refer to the conspiracy he claimed to uncover when working at a local hospital from 1998 to 2000.
The author wrote the conspiracy that began when he "discovered a refrigerator full of dismembered body parts & organs wrapped in plastic in the morgue of the largest non-metropolitan healthcare organization in the United States of America."
Curtis wrote that he was trying to "expose various parties within the government, FBI, police departments" for what he believed was "a conspiracy to ruin my reputation in the community as well as an ongoing effort to break down the foundation I worked more than 20 years to build in the country music scene."
In one post, Curtis said he sent letters to Wicker and other politicians.
"I never heard a word from anyone. I even ran into Roger Wicker several different times while performing at special banquets and fundraisers in northeast, Mississippi but he seemed very nervous while speaking with me and would make a fast exit to the door when I engaged in conversation ..."
He signed off: "This is Kevin Curtis & I approve this message."
The White House and Capitol Hill were on alert after initial tests Wednesday showed that suspicious letters contained ricin, a deadly toxin.
As federal authorities investigated the letters to Obama and Wicker, several other senators reported that they, too, had received suspicious mail. The reports prompted U.S. Capitol Police to close portions of two congressional office buildings for a brief time.
Both letters bore a Memphis postmark, law enforcement authorities said. In an intelligence bulletin obtained by the Associated Press, the FBI reports that both letters say: "To see a wrong and not expose it, is to become a silent partner to its continuance." Both are signed, "I am KC and I approve this message," wording that candidates use at the end of their broadcast political ads.
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 in a telephone interview.
Ricky Curtis said his cousin had written about problems he had with a cleaning business and that he felt the government had not treated him well, but he said nobody in the family would have expected this.
Ricin can be deadly if ingested or inhaled, but it's generally considered ineffective as a weapon for mass terrorism because it is very difficult to put it into an airborne form.
The letters to Obama and Wicker both were intercepted at off-site screening facilities where official mail is checked for potential contaminants.
Obama was briefed on the suspicious letters Tuesday night and again Wednesday morning, said White House press secretary Jay Carney.
Both the FBI and the White House stressed that there is no indication of any connection between the letters and Monday's twin bombings at the Boston Marathon. Carney cautioned that Americans shouldn't jump to any conclusions.
"Before we speculate or make connections that we don't know ... we need to get the facts," Carney said.
The letter to Wicker was discovered first, on Tuesday, and Capitol Police said it contained a "white granular substance." The letter to Obama was revealed Wednesday morning.
Another suspicious package was received Wednesday morning at the Washington offices of Sen. Richard Shelby, R-Ala., according to Shelby's spokesman Jonathan Graffeo. He said the package is being investigated by Capitol Police and it was not known if it was similar to the ones addressed to Obama and Wicker.
Sen. Carl Levin, D-Mich., issued a statement Wednesday saying that a suspicious letter was received at his Saginaw, Mich., field office. Thursday morning, Levin said he was advised by the FBI that preliminary tests of the letter turned up negative and that his office is open as usual.
Also Wednesday, authorities evacuated the Phoenix office of Sen. Jeff Flake, R-Ariz., after receiving reports of suspicious letters. Flake later announced that investigators had determined that there was no threat.
All routine mail to Congress and the White House is screened off-site, FBI spokesman Paul Bresson said, but those tests can produce inconsistent results. If the tests indicate the possibility of a biological agent, the material is sent to an accredited laboratory for further analysis, and only those tests can confirm the presence of a biological agent.
Ricin is derived from the same plant used to produce castor oil. Because it is not readily put in the form of an aerosol that spreads easily through the air, it is considered far less worrisome as a weapon than anthrax, the substance mailed to members of Congress in shortly after the Sept. 11, 2001, terror attacks in an episode that killed five and sickened 17 others.
"It's high school chemistry to make it, but it's not a serious bio threat," said Randall Larsen, former executive director of the WMD Commission, which was set up by Congress to investigate threats posed by weapons of mass destruction. "You won't find bio-terror experts getting all upset by ricin. It's usually (used by) nut jobs doing something to try to get attention from people."
Michael Osterholm, a former bioterrorism adviser to the George W. Bush administration who heads the Center for Infectious Disease Research and Policy at the University of Minnesota, called the interception of the ricin letters "a success story."
"It's a horrible situation that it happened but it's a success that it was found," Osterholm said. "The ability to identify ricin in a letter was not in place before 2001. The U.S. mail is being tested for things like this. This was not a letter that got opened and someone said, 'Oh my gosh.'"
Handling a letter would be unlikely to give someone a lethal dose of ricin, Osterholm said. The poison is most dangerous when inhaled; getting it on one's fingers wouldn't pose that sort of risk. However, if someone is poisoned with ricin, there is no treatment and it can kill in one to three days.
Contributing: Mary Orndorff Troyan, Deirdre Shesgreen, Deborah Barfield Berry and Maureen Groppe of the Gannett Washington Bureau; Liz Szabo, Jim Michaels, Gregory Korte and Natalie DiBlasio of USA TODAY; The Associated Press