(VOVWORLD) - An envelope addressed to the White House contained a substance identified as ricin, a deadly poison, several media outlets reported on Saturday, citing a federal official briefed on the matter.
 The White House in Washington, D.C. (Photo: Xinhua/VNA) |
The envelope believed to have come from Canada was intercepted at a government mail center before it arrived at the White House, the New York Times, CNN and Wall Street Journal reported.
Ricin is found naturally in castor beans but it takes a deliberate act to convert it into a biological weapon. Ricin can cause death within 36 to 72 hours from exposure to an amount as small as a pinhead. No known antidote exists.