In a tweet published shortly after 10 a.m., the Tennessee Bureau of Investigation confirmed the development in the high-profile case.
Siskiyou County sheriff's officials earlier Thursday had confirmed to ABC News that Cummins' vehicle had been discovered. The county is located along the Oregon border in the Shasta Cascade region.
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Cummins, a 50-year-old husband and grandfather, is accused of aggravated kidnapping and sexual contact with a minor.
MEDIA: We are planning for an afternoon news conference. Details will be announced as soon as possible. pic.twitter.com/Tw7IKNWZ38— TBI (@TBInvestigation) April 20, 2017
The disappearance of Elizabeth, 15, initially prompted law-enforcement officials to issue an Amber Alert.
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The two vanished March 13 after Cummins was investigated by the school system when another student reported seeing the then-married teacher kiss the girl at the Culleoka Unit School.
Two days later, surveillance images from a Walmart in Oklahoma City showed Cummins and the girl purchasing food items in the store with cash, the Tennessee Bureau of Investigation said. The statement said the images captured showed Cummins had altered his hair to appear darker and the girl may have changed her hair color to red.
Court papers filed recently in the girl's disappearance said she was afraid of the teacher and thought she would face repercussions at school if she resisted him.
According to Elizabeth's family's lawyer, Cummins was allowed to continue working at the school for two weeks after he was reported kissing the student.
Last month, Cummins' wife of 31 years filed for divorce. Court records show that Jill Cummins sued her then-missing husband on the grounds of irreconcilable differences and inappropriate marital conduct.
The wife, who works for the Maury County school system, said she had not seen her husband since March 13. They have two children together.
The Associated Press contributed to this report.