(WAFF) - Elizabeth Thomas disappeared from Columbia, Tennessee on March 13. She's believed to be with her former teacher, Tad Cummins.
Josh DeVine with the Tennessee Bureau of Investigation confirms Thomas was in Decatur the morning she left Tennessee.
"We have not confirmed it was a phone ping that placed her in Decatur, Alabama the Monday that she disappeared. We have, however, confirmed there is information we developed over the course of the investigation that places her in Decatur, Alabama on Monday," said DeVine.
The only other confirmed clue is a sighting in Oklahoma City on March 15.
Investigators say Thomas and Cummins could be anywhere.
FBI spokesman Paul Daymond says one tip could crack this case, or any case.
"You may have heard the expression if you see something say something. That is certainly applicable anytime you have an amber alert or a missing child. So if you see anything. Anything you think is them. If you see the vehicle. by all means call 911, because it may be that one piece of information that makes the difference," he said.
Daymond says this step is vital, even if you don't want to be involved. He says you can make the call anonymously.
"Really, all we're looking for, law enforcement just wants your information. You can remain anonymous. Just call 911 and say 'Hey I saw someone who looked like that person at this address or this location,'" Daymond said.
DeVine echos the advice and says not to wait.
"Time is absolutely of the essence. We want to get local law enforcement as soon as we possibly can," he said.
"Remember that phrase, 'If you see something, say something.' Because you may not think it's anything, but it may be that piece of information that puts all of the information together for law enforcement," said Daymond.
If you have information about Elizabeth's time in Decatur, the TBI wants you to call them directly through the tipline at 1-800-TBI-FIND.
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