The Defense Department’s top spokeswoman on Wednesday said the suspicious substance found in envelopes sent to the Pentagon earlier this week was castor seeds, which can be made into the toxin ricin.
“According to our preliminary analysis, the substance was castor seeds, from which ricin is derived. The FBI is still investigating,” Dana White said in a statement to The Hill.
Castor seeds are only dangerous if swallowed, but they can be used to make a poisonous pure form of ricin.
{mosads}The Pentagon Force Protection Agency detected the suspicious substance in two letters during mail screenings on Monday at the building’s remote screening facility.
One envelope was addressed to Defense Secretary James Mattis and the other was meant for Chief of Naval Operations John Richardson.
Officials suspect a former Navy sailor is behind the multiple parcels, Fox News reported Wednesday.
In addition, suspicious envelopes addressed to President Trump were intercepted on Monday by the U.S. Secret Service.