WATCH: Federal agents searching the Utah home of ricin scare suspect

WATCH: Federal agents searching the Utah home of ricin scare suspect

Transcript for Federal agents searching the Utah home of ricin scare suspect

Now, to another developing story right now. What appears to be a major break in that ricin scare. Suspicious envelopes, among them letters addressed to the president and the defense secretary. And tactical teams are, right now, outside a home in Logan, Utah. There is a man in custody at this hour. And ABC’s chief justice correspondent Pierre Thomas on what we know about him so far. Reporter: Tonight, federal agents at the Logan, Utah, home of a man they suspect of mailing those threatening letters to the white house and Pentagon. As a precaution in case they encountered the deadly poison ricin, authorities proceeded carefully in tactical gear, concerned about the potential of toxic chemicals. The FBI is questioning a suspect, described as a former Navy sailor, after someone tried to send a letter to president trump, and two others to secretary of defense James Mattis and chief of naval operations John Richardson. Field tests of the Pentagon letters indicated the possible presence of ricin. These cases usually are easy to solve, because people who put substances like this in the mail aren’t very sophisticated. Reporter: But tonight, the Pentagon’s spokesman says the letters appear only to contain castor bean seeds, which has to be processed in order to be turned into ricin. Still, authorities are being extremely careful and charges could be filed if it is determined the letters were intended as a threat. David, the suspect has been identified as William Clyde Allen III. He served as a Navy apprentice, fireman’s apprentice from 1998 to 2002. Sources say he’s expected to be charged with threatening communications. David? Pierre Thomas, thank you. And next, to the tornado

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