The FBI on Wednesday arrested a Navy veteran suspected of sending two envelopes sent to the Pentagon this week that contained raw materials for the deadly poison ricin.
The man, William Clyde Allen III, was detained at a home in Logan, Utah.
Two envelopes addressed to US defence secretary Jim Mattis and to the chief of the US Navy, Adm John Richardson, set off alarms in a mail screening facility outside the Pentagon Monday. No one was injured.
Defence officials had suspected that the letters contained ricin, but a Pentagon spokeswoman said Wednesday that they actually contained castor beans, the raw material from which ricin is made. She said the FBI was investigating. Another letter suspected of containing ricin was sent to US president Donald Trump at the White House on Monday, but was intercepted by the Secret Service.
In a statement the Secret Service said no one was injured. FBI agents raided a single-family house in Logan, about 80 miles north of Salt Lake City, taking into custody a man described in local news reports as a Navy veteran.
Agents closed down a block of North 200th Street, a quiet road with small homes and a large Mormon church.
The FBI did not respond to requests for comment, but told The Herald Journal of Logan that the house posed no risk to the public. Castor beans, used to make castor oil, pose little danger, but refined ricin, extracted from mashed castor beans, is so toxic that ingesting or inhaling a few grains can be fatal.
During World War I, the United States investigated developing a chemical weapon using clouds of ricin dust.
A Justice Department spokeswoman in Salt Lake City said federal prosecutors had authorised a probable-cause arrest for Allen, 39.
Prosecutors have 48 hours to file charges. Allen served in the Navy from 1998 to 2002 as a low-ranking damage-control fireman apprentice on supply and support ships, Navy officials told Military Times. Nothing in his record indicates he served in combat.
A Facebook account matching Allen's name and location contained posts about Christianity and the golden ratio, but also a post suggesting he had watched online videos about extracting cyanide from apple seeds. One of the account's latest posts, on Tuesday evening, stated, "The 99 per cent are just a bunch of Zero'$." – New York Times