[lin_video src=http://eplayer.clipsyndicate.com/embed/player.js?aspect_ratio=3x2&auto_next=1&auto_start=0&div_id=videoplayer-1366237862&height=480&page_count=5&pf_id=9624&show_title=1&va_id=4021415&width=640&windows=2 service=syndicaster width=640 height=480 div_id=videoplayer-1366237862 type=script]WASHINGTON, D.C. (WIAT) — Only two days after two bombs exploded at the Boston Marathon killing three people and wounding dozens more, a new threat has emerged.
Several letters containing traces of ricin were intercepted.
One of the letters was addressed to President Obama, another was addressed to Mississippi Senator Roger Wicker and a third letter was addressed to Alabama Senator Richard Shelby.
The FBI has confirmed that the letters sent to President Obama and Senator Wicker both tested position for ricin, a poison that can be made from the waste material left over from processing castor beans.
The three letters have authorities on Capitol Hill on high alert.
According to police, the letters addressed to both Senator Wicker and President Obama were postmarked in Memphis, Tennessee. Neither of the letters contains a return address.
The FBI says the testing on the substances will take 24 to 48 hours.
In 2004, a letter found in the mailroom of then-Senate Majority Leader Bill Frist contained traces of ricin.
The Center for Disease Control and Prevention says that if ricin is made into a partially purified material or refined into a terrorist or warfare agent, it could be used to expose to people through the air, food or water.
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