Authorities say at least two suspects accused of plotting attacks involving deadly biological toxins are former federal employees.
Court records state that one suspected member of a Georgia militia group worked for the U.S. Department of Agriculture.
Authorities said another man who was arrested worked for a contractor at the federal Centers for Disease Control.
Prosecutors said that 65-year-old Ray Adams used to work as a lab technician for a USDA agency known as the Agricultural Research Service.
Court documents state that CDC officials confirmed that another suspect, 68-year-old Samuel Crump, worked at the CDC in the past for a contractor that did maintenance at the Atlanta-based agency.
Prosecutors say the men were part of a group that tried to obtain explosives and aimed to produce ricin, a lethal toxin.