Authorities said they found pipe bombs and a jar containing the potentially deadly poison ricin while searching a home in suburban Nashville.
The ricin was found sealed in a baby food jar in a shed at the home of William Micheal Matthews, according to a joint statement Thursday from Nashville police, the FBI, Bureau of Alcohol, Tobacco and Firearms, and health officials.
Officials said the jar was sealed and they do not believe the neighborhood was threatened, although the house remained cordoned off Thursday night. An FBI hazardous material team was expected to arrive Friday morning to continue sweeping the property.
Authorities first searched the shed Wednesday after receiving a tip from Matthews' estranged wife. They also found five gun silencers, a bowl containing ricin residue and bomb-making materials.
Matthews, 55, began serving a nine-month jail sentence last week for violating orders of protection taken out by his wife while he was being treated for substance abuse. No charges had been filed Thursday night, but authorities said they were talking with the U.S. Attorney's office.
It was not immediately known whether Matthews had a lawyer. He was represented on his domestic violations by different public defenders, according to court records.
"It's totally out of character for Mike (Matthews)," neighbor Tommy Smith told WSMV-TV in Nashville while authorities blocked off the street Thursday. "We're totally floored."
Matthews was a longtime Metro Nashville employee who recently left his job working in the city's drug court testing laboratory after female co-workers filed sexual harassment complaints against him, according to city personnel records examined by the television station.
Ricin is a poisonous protein that can be used as a biological weapon. As little as 500 micrograms of the protein, roughly the amount that fits on the head of a pin, is enough to kill an adult, according to the federal Centers for Disease Control and Prevention.