Suspected ricin detected in mail sent to Trump, Pentagon

Envelopes addressed to President Donald Trump and the Pentagon contained a substance suspected to be ricin, a law enforcement source told CNN.

"The Secret Service can confirm receipt of a suspicious envelope addressed to the president on Oct. 1, 2018," a Secret Service spokesman said. "The envelope was not received at the White House, nor did it ever enter the White House."

Extracted from castor beans, ricin is a highly toxic compound.

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