Two envelopes suspected of containing ricin poison, one addressed to Defense Secretary James Mattis, have been identified in the Pentagon’s Central Processing Center, according to a U.S. official.
The envelopes were addressed to Mattis and Chief of Naval Operations Adm. John Richardson, the official said.
The pieces of mail, which were flagged as part of the Pentagon’s normal processing procedures, are being examined to determine whether they test positive for the deadly poison, the FBI said in a statement.
Meanwhile, all U.S. Postal Service mail received at the Pentagon facility Monday is under quarantine, the Department of Defense said in a statement.
That mail poses no threat to Pentagon personnel, the statement continued.
The Pentagon’s Central Processing Center is located on the Pentagon compound in Arlington, Virginia, but not directly attached to the main building. The envelopes did not enter the Pentagon itself.
Ricin is a poison found naturally in castor beans that can be purified or refined into an agent used to expose people through the air, food or water, according to the Centers for Disease Control and Prevention.
While ricin poisoning is not contagious, the agent itself can be transferred when located on a person’s body or clothing.