Tennessee Bureau of Investigation agents are still looking for 15-year-old Elizabeth Thomas, who they said was taken by her teacher, 50-year-old Tad Cummins. As of Friday, the TBI said during a news conference that Cummins had been added to the TBI's Top 10 Most Wanted list for kidnapping Thomas.

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The Tennessee Bureau of Investigation said Thomas was last seen Monday morning at 8 a.m. at Shoney's in Columbia, Tennessee, after a friend dropped her off.

She is described as white, with blonde hair and hazel eyes, 5 feet 5 inches tall and 120 pounds, and was last seen wearing a flannel shirt and black leggings.

She was initially thought to be in the area of Decatur, Alabama, with Cummins.

Cummins is described as white, 6 feet tall and 200 pounds, with brown hair and brown eyes. He is believed to be armed with two handguns and driving a Silver Nissan Rogue, with Tennessee tag 976ZPT

Agents said they learned Thomas was in Decatur, Alabama by 3:06 p.m. Monday.

On Wednesday, TBI released video of Cummins, who appears to be at a Tennessee gas station before abducting Thomas.

The Tennessee Bureau of Investigation released the following statement:

We're continuing to track down every possible detail leading up to the disappearance of Tad Cummins and Elizabeth Thomas. Here's surveillance video of Cummins, filling his Nissan Rogue with gasoline, which we believe he did just prior to picking up Thomas at a nearby Shoney's, which is the last known sighting of Thomas. The 15-year-old remains the subject of a Tennessee AMBER Alert.

Agents said Cummins will now face a charge of sexual contact with a minor connected to an alleged sexual interaction between himself and Thomas at the school where he taught and she was a student.

District Attorney General Brent Cooper announced Friday that Cummins also faces an aggravated kidnapping charge.

By Thursday,  the TBI said it remained "extremely concerned" for the well-being of Thomas.

“Since issuing the AMBER Alert at approximately 6:00 CST Tuesday, the TBI has received approximately 120 leads,” the organization said in an update Thursday. “None has produced any credible sightings about the whereabouts of either individual. Because of the shockingly low number of tips, the TBI has concluded the individuals are likely out of the view of the general public or outside the original net cast across the southeast to notify the public about their disappearance. Having last been seen on Monday morning, the individuals could, frankly, be anywhere.”

WBIR reported on Thursday that a second nationwide be on the look out, or BOLO, alert has been issued.

The Maury County School District fired Cummins on Tuesday. He was initially suspended when the allegations surfaced.

The TBI was able to determine Cummins secured a title loan for a personal vehicle leading up to his disappearance and got $4,500 in cash.

If you have seen either Cummins or Thomas, call 1-800-TBI-FIND (1-800-824-3463).

The Cox Media Group National Content Desk contributed to this report.