Letter sent to Obama tests positive for ricin, officials say

By Pete Williams, Kristen Welker and Erin McClam, NBC News

A letter addressed to President Barack Obama tested positive for the poison ricin and was from the same sender who mailed a letter to a senator that also tested positive, officials told NBC News on Wednesday.
The letter to Obama was intercepted at an off-site White House mail facility and was being tested further, the FBI said. A federal law enforcement official said that the letter was “very similar” to one addressed to Sen. Roger Wicker, R-Miss.
Federal officials told NBC News that they believe they know who sent the letters, but no arrest was made because authorities were waiting for further test results.
Ricin is made from castor beans and can kill within 36 hours. There is no antidote. Some threatening letters simply contain ground castor beans, resulting in a positive field test for ricin without the concentrated poison. Results from full laboratory tests are expected in the next 24 to 48 hours.

Filters at a second government mail screening facility also tested positive for ricin in preliminary screening Wednesday.

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