Updated

Authorities in Tennessee investigated a new possible sighting Thursday of an ex-school teacher and a student he's accused of kidnapping that turned out to be an unfounded report.

Officials have been hunting for 50-year-old Tad Cummins and 15-year-old Elizabeth Thomas, who last was seen March 13.

The Collierville Police Department, located in the western part of the state, said earlier in the day the sighting was reported around 12:30 p.m. local time at Shell gas station. Thomas and Cummins were reported to be traveling in a white Chevrolet panel van with a ladder rack and possibly "a blue or aqua colored tube on top."

Shabana Mavani, an employee at the gas station where the sighting possibly occurred, told Fox 17 police came to the store and showed them a picture of Cummins and Thomas. Mavani said didn't even know about them until police showed employees the photos.

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Mavani said two people bearing similar resemblance came into the store, purchased some items, and that "the man looked agitated and ready to leave" while the girl "seemed calm and comfortable."

The Tennessee Bureau of Investigation however determined the reported sighting was not Thomas and Cummins.

"The TBI has determined the reported sighting in Collierville, TN was not, in fact, Tad Cummins and Elizabeth Thomas," TBI spokesman Josh DeVine said in a tweet.

Cummins was added to Tennessee’s Most Wanted List after he was suspected of kidnapping Thomas earlier this month. Authorities issued an Amber Alert for a silver Nissan Rogue with license plate 976ZPT.

Investigators believe Cummins may have abducted the girl to "potentially sexually exploit her."

Cummins was Thomas' former teacher and is wanted for having sexual contact with the teen while teaching at the Culleoka Unit School as a health science teacher.

Read more from FOX 17 Nashville.

Read more from FOX 13 Memphis.