A Knoxville woman was arrested Thursday after it is alleged she racked up over $12,000 in unauthorized debit card transactions. According to court documents on December 5th law enforcement officers spoke with the victim who told officers 38-year-old Christa Lancial had been staying with her and helping her while her boyfriend was out of town. The victim would give Lancial a debit card and pin number to run errands and buy groceries for the victim. The victim and her boyfriend discovered unauthorized transactions on their bank statements. Lancial told officers she had used the debit card but said she was authorized to do so and the victim knew. She also admitted she would tell the victim about the withdrawals but also knew the victim has an illness that causes forgetfulness. Officers determined the ATM withdrawals and any transaction outside of the duties to help the victim were unauthorized. The total amount of unauthorized money stolen came to $12,439.75. Lancial was arrested and charged with theft 1st degree, a class C felony.