NASHVILLE, Tenn. (WKRN) – As the search for missing Maury County teen Elizabeth Thomas continues, News 2 spoke with a retired FBI special agent about how investigators piece together a limited number of clues.

Dan Hodges was with the FBI for over 30 years and now owns Hodges and Associates, a investigation firm in Nashville.

Hodges spoke of how Thomas’ disappearance is being investigated by the Tennessee Bureau of Investigation.MORE: New photos, surveillance video released in AMBER Alert case

“The TBI is a very professional outfit, I know they have worked long and hard on this around the clock, I enjoyed working with them over the years and I know they have explored every avenue they can, they have checked the credit cards, the cell phone and the vehicle and all of that,” said Hodges.PHOTOS: AMBER Alert for Elizabeth Thomas

“He has dropped off the grid, that makes me think he’s in rural area somewhere, maybe camping,” added Hodges.

The number of tips the TBI have received is small compared to other cases like Thomas’.

“Usually you get thousands and thousands of tips, most of them are erroneous but they do run every one of them down. It’s kind of dried up in the last several days, there is not much coming in, no spottings, that’s what’s frustrated law enforcement and I can really understand that,” said Hodges.

Hodges mentioned Thomas may have developed Stockholm syndrome, where a victim begins to identify with their captor.

“Even if she is a captor, she can start to identify with this man, even if he is threatening to cause her harm. And the police are aware of all of this, the TBI for sure have researched this for years and years, it’s hard to say how it will surface. I think it’s going to rely on a citizen.”

Thomas is a 15-year-old white female, with hazel eyes, stands 5 feet tall and weighs 120 pounds. She was last seen wearing a flannel shirt and black leggings.

Cummins is a white male, who stands 6 feet tall, weighs approximately 200 pounds, and has brown hair and eyes. He’s believed to be armed with two handguns.

He faces kidnapping in the AMBER Alert case and is also charged with sexual contact with a minor after he allegedly kissed Thomas at school earlier this year.

Last week, the TBI added Cummins to the state’s ‘Top 10 Most Wanted’ list. There is a $1,000 reward for information leading to his capture. The TBI would urge the public to remain vigilant and report any information that may prove beneficial in the ongoing search to 1-800-TBI-FIND.

Click here for more on the AMBER Alert for Elizabeth Thomas.