A man declared dead 16 years ago was charged Thursday with the recent kidnapping of a 12-year-old Nevada girl whose body was found by hunters in Louisiana.

Authorities said 53-year-old Thomas Steven Sanders, legally dead in Mississippi since 1994, apparently had been living in Las Vegas where he met Lexis Roberts and her mother, Suellen Roberts, a few months ago. Lexis Roberts' remains were found in east-central Louisiana in early October.

Relatives told investigators the girl and her mother had known Sanders for two or three months, said Robert King, the FBI agent in Alexandria heading up the investigation.

Investigators are trying to piece together what happened to Sanders since relatives declared him dead after not hearing from him for seven years.

"He just walked away one day and never came back," King said.

However, officials said security cameras showed Sanders, who has a record of crimes against children, buying ammunition on Sept. 3 at a Wal-Mart in Las Vegas. The bullets he bought were consistent with the weapon used to kill Lexis, police said.

Sheriff's officials in Arizona's Coconino County told the Las Vegas Review-Journal that the girl was seen Sept. 4 with her mother and Sanders at the Bearizona Drive-Thru Wildlife Park off Interstate 40 in Williams, Ariz. Her mother is also missing. He was discovered to be alive only since the girl disappeared. Authorities are trying to track down family in Mississippi and Louisiana.

Sanders was last seen driving a silver 2001 Kia Spectra with damage on the passenger side. It may have Nevada plates, or stolen plates, officials said.