A Mississippi man has been arrested as a suspect in connection to the mailing of two letters sent to President Obama and Sen. Roger Wicker, R-Miss., that initially tested positive for ricin, Fox News confirms.
FBI Special Agent in Charge Daniel McMullen said the man was arrested Wednesday at approximately 5:15 p.m. CT. It is unclear if charges are getting filed tonight or if they will be filed tomorrow.
He was arrested at his Corinth, Miss., home following an investigation conducted by the FBI Joint Terrorism Task Forces in Memphis, Tenn., and Jackson, Miss., the U.S. Capitol Police, and the U.S. Postal Service, the U.S. Secret Service.
The suspect has been identified as Paul Kenneth Curtis of Tupelo, Miss., a source told Fox News. Tupelo is also the hometown of Wicker and his wife.
The FBI confirmed earlier Wednesday that a letter addressed to President Obama had "preliminarily tested positive" for ricin, a day after lawmakers said another letter sent to the Capitol Hill office of Sen. Roger Wicker tested positive for the same substance.
The warnings came amid a flurry of reports on suspicious packages. Fox News learned of several suspicious packages or envelopes in various Capitol Hill office buildings, and Capitol Police said three packages that were flagged had been removed.
Separately, the office of Sen. Carl Levin, D-Mich., reported a "suspicious-looking letter" at one of the senator's Michigan offices; and a spokesman for Sen. Jeff Flake, R-Ariz., reported a "suspicious letter" was intercepted at Flake's Phoenix office. Authorities were also called to the Dallas office of Sen. John Cornyn, R-Texas, over what was described only as "a piece of mail" -- but field tests later came back negative.
According to a Homeland Security Department handbook, ricin is deadliest when inhaled. It is not contagious, but there is no antidote. A senior Congressional source familiar with the inquiry into the letters sent to President Obama and Sen.Wicker told Fox News that the ricin was "low grade" and "not weaponized."
The package alerts compounded security concerns in the wake of the letter incidents and the Boston bombing, which the FBI has said do not appear to be related.
Both of the initial suspicious letters were apparently intercepted on Tuesday. They never reached the Hill or the White House.
An FBI bulletin obtained by Fox News said the letter sent to Obama is still being screened, though it initially tested positive.
The bulletin said both letters included the phrase: "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."
The envelopes had Tennessee postmarks, but no return address.
Sources say officials are familiar with the person believed to have sent the letter as the person has sent other letters before.
The mail-screening system was established after the Anthrax attacks of 2001 that closed the Hart Senate Office Building.
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Fox News' Mike Emanuel and Chad Pergram, and the Associated Press contributed to this report.
