The FBI has joined the search for a missing Madison County toddler, but authorities say they're still not sure what happened to her.
Police began looking for 2-year-old Myra Lewis Saturday afternoon after family members realized she was missing. She may have been gone from her rural Camden home for four hours by that time.
An Amber Alert was issued Sunday, and family members said Monday they believed she was kidnapped. But Madison County Sheriff Randy Tucker says authorities aren't sure.
Tucker said Tuesday that authorities have searched 4 square miles around the family home, using dogs, aircraft and more than 300 people.
The sheriff urges people to contact authorities with tips "no matter how insignificant."