WASHINGTON - According to CNN, congressional and law enforcement sources say that an envelope that tested positive for the deadly poison ricin was intercepted at the U.S. Capitol's off-site mail facility in Washington on Tuesday.
"After the envelope tested positive in a first routine test, it was retested two more times, each time coming up positive, the law enforcement source said. The package was then sent to a Maryland lab for further testing," CNN reports.
According to Fox News, the letter was addressed to the office of Sen. Roger Wicker (R-Miss.).
No information has been released regarding who sent the letter.
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