JACKSON, Miss. (AP) - The FBI is investigating at least three recent cases involving ricin-laced letters sent to public officials. And experts say some of them may be copycat attacks made possible by the relative ease of creating the poison.
The key ingredient - castor beans - comes from plants that grow wild in the United States. Instructions for extracting the poison from the beans can be found on the Internet.
And it doesn't require a chemistry degree or sophisticated lab equipment.