In an open letter Thursday, the family of missing Tennessee teenager Mary Catherine Elizabeth Thomas said they were “desperate” for information about her disappearance and again urged people to come forward if they know something.
“The last ten days have been the most difficult in the life of the Thomas family,” they said in their letter, which was released Thursday via their attorney and obtained by PEOPLE.
“The information that we need is not only what people have seen and heard after Elizabeth’s disappearance, but also from before [she went missing],” the family said.
Fifteen-year-old Thomas, who goes by Elizabeth, was last seen on March 13 in Maury County, Tennessee, after a friend dropped her off at a local Shoney’s.
The teen remains the subject of a multi-state AMBER Alert, and authorities suspect her former teacher Tad Cummins kidnapped her.
Cummins, 50, worked as a health science teacher at Thomas’ high school in Maury County. He was fired last week over accusations about his relationship with her, after he and Thomas disappeared, authorities said.
A warrant has been issued for Cummins’ arrest on charges of aggravated kidnapping and sexual contact with a minor.
The latter charge stems from an alleged kiss between him and Thomas on Jan. 23, on school property, according to the Tennessee Bureau of Investigation.
Jason Whatley, the family’s attorney, claimed last week that the school district did not suspend Cummins from work when the alleged interaction was reported on Jan. 24.
On Feb. 6, two weeks after the alleged kiss, Whatley said he sent a letter to the school district on behalf of the family, expressing their concerns — and Cummins was suspended that same day.
In their new letter, however, Thomas’ family underlined their respect for the educational community, while thanking law enforcement and the local community “and beyond” for their “tireless” efforts.
“The family has been overwhelmed with the kindness shown to us by the Maury County community and beyond,” the family said. “We humbly ask that you continue to pray as we do our best to cope with the emotional weight of Elizabeth’s abduction.”
“It is important to the Thomas family to emphasize that none of the reports about possible mistakes made regarding Tad Cummins prior to Elizabeth’s disappearance are relevant to what we are doing now,” the family said.
“Our focus should be on finding Elizabeth. Period.”
“We know that each teacher and administrator at Maury County Schools mourns as we do over this tragedy and wishes daily for Elizabeth’s safe return,” the letter continued. ” … Whatever questions about how issues were handled when Elizabeth was in school are distant and secondary and, in many ways, distracting, to the core issue of dinging her.”
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Whatley previously told PEOPLE that Cummins allegedly “groomed” Thomas.
On the morning she disappeared, Thomas told her sister to call the police if she didn’t return home by 6 p.m., he said.
Thomas’ older sister, Sarah, told PEOPLE that her sister would talk about leaving.
“She said months before that she had to get out of here, we have to get out of here [and] I can’t take this,” Sarah said.
On Tuesday, Tennessee officials released a photo of Thomas and her alleged captor in his classroom in January.
Thomas’ father, Anthony, told PEOPLE that Cummins “built up a system where she was dependent on him.”
According to Anthony, Cummins helped Elizabeth with homework and “[gave] her money, bought a microwave so she would heat food up in his room [and] try and get her out of trouble.”
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Elizabeth was last seen wearing a flannel shirt and black leggings. She is 5 feet 5 inches inches tall and weighs 120 lbs., with blonde hair and hazel eyes.
Cummins was seen driving a Silver Nissan Rogue with Tennessee license plate 976ZPT, according to the TBI. He is 6 feet tall and weighs 200 lbs., with brown hair and eyes.
The Thomas family concluded their letter Thursday with a short declaration: “Elizabeth must be found. Time is of the essence.”
Anyone with information on Cummins or Elizabeth should call the TBI at 1-800-TBI-FIND.