WASHINGTON (AP) - The FBI says the letters sent to President Barack Obama and Sen. Roger Wicker are related and are both postmarked out of Memphis, Tenn., dated April 8.
In an intelligence bulletin obtained by The Associated Press, the FBI says the letters both say: "To see a wrong and not expose it, is to become a silent partner to its continuance. Both letters are signed, "I am KC and I approve this message."
The FBI says the substance in both letters have preliminarily tested positive for Ricin, a potentially fatal poison.
Both the letters to Wicker, R-Miss., and to Obama were intercepted at off-site mail facilities. The FBI says it is pursuing investigative leads to determine who sent the letters.
Meanwhile, parts of the U.S. Capitol were evacuated on Wednesday at lunch time after authorities announced suspicious packages on the first and third floors of the Hart Senate Office Building, and a suspicious envelope in the Russell Senate Office Building at the office of Sen. Richard Shelby of Alabama.
CNN reports that Capitol Hill Police are questioning a man with a backpack in the area of the Hart office building. The man raised suspicion with the content of his backpack and how he responded to police questions, two Capitol Hill police officers said.
The man's backpack contained more sealed envelopes, one of the officers said. One of the Capitol Hill police officers on the scene said the backpack is being X-rayed.