iStock/Thinkstock(WASHINGTON) — The substance found in the envelopes sent to the Pentagon, White House and Sen. Ted Cruz’s office were castor seeds and not ricin, according to a U.S. official familiar with the investigation.
Castor seeds are what the poison ricin is derived from.
The official said that one of the four envelopes had a return address, which the FBI is now pursuing as a lead.
The development comes one day after two envelopes suspected of containing ricin poison were identified in the Pentagon's Central Processing Center, according to a U.S. official.
The Secret Service reported Monday that one of the envelopes was addressed to Defense Secretary James Mattis. The other suspicious envelope was addressed to President Donald Trump, though that envelope was not received nor did it enter the White House.
The envelopes found at the Pentagon's mail center were addressed to Mattis and Chief of Naval Operations Adm. John Richardson, the official said. Those pieces of mail, 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.
ABC affiliate KTRK-TV reported that two people were hospitalized after an envelope with a powdery substance was sent to Cruz's campaign office in Houston.

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