Ricin Confirmed in Letters to President Obama & Senator Wicker; Suspicious Letters Also Received by Other Senators

A letter sent to Mississippi Senator Roger Wicker tested positive for the poisonous substance ricin, and initial testing also reveals that ricin was included in a letter addressed to President Barack Obama.

Several U.S. Senators have confirmed that they have receive suspicious letters, with at least one addressed to Senator Roger Wicker confirmed as having included the poisonous substance ricin. The Secret Service is also investigating a letter that was sent to President Barack Obama, which they state that initial testing reveals also contained ricin.

Ricin, which is derives from the castor bean plant, is considered to be the most poisonous, naturally occurring substance. The bean part of the plant is what is poisonous to humans, animals, and insects. The "mash" from the processing of castor beans is ricin, which can be a powder, a mist, or a pellet. It can also be dissolved in water or a weak acid.

A letter mailed to Sen. Wicker that was postmarked in Memphis was intercepted at an off-site Capitol mail facility, and was found to contain a "white granular substance". The letter was quarantined before preliminary test showed that the substance was ricin. The letter has been sent to the FBI for further investigation. A suspect has been identified.

A second suspicious package was received on Wednesday morning at the Washington D.C. offices of Sen. Richard Shelby (R-Ala.). A spokesman for the senator says that the package is being investigated by Capitol Police. It is not yet know if it was similar to the one addressed to Wicker and Obama, which contained ricin.

Sen. Carl Levin (D-Mich.) also revealed that a suspicious letter was received Wednesday morning at his field office in Saginaw, Mich. He noted that the staffer who received the letter did not open it and turned it over to authorities, who are investigating.

The Secret Service is also investigating a letter that contained a "suspicous substance" that was addressed to President Obama. FBI spokesman Paul Bresson revealed that the letter tested positive for ricin. It was sent to Obama on Tuesday and was intercepted at the White House mail screening facility.

The White House mail screening facility is not located near the White House and is in a remote facility.

White House Press Secretary Jay Carney says that President Obama has been briefed on the suspicious letters on Tuesday night and again on Wednesday morning.

The FBI says that there are no indications that the letters are at all connected to the double bombing in Boston on Monday, and Carney cautions that Americans should not jump to any conclusions just yet.

A suspicious on Wednesday also prompted the Capitol Police to close off access to the Hart Senate Office Building. The package was reportedly in the atrium of the Hart building. People on other floors of the building have been asked to go into their offices.