An Iowa teen who was charged with killing her accused rapist has gone missing after she escaped her probation center, officials confirmed. 

On Friday, Pieper Lewis escaped the Fresh Start Women’s Center after cutting off her electronic monitoring tracking device, Jerry Evans, the executive director for the 5th Judicial District, told CBS News in a statement. 

“At this time, her whereabouts are unknown,” Evans said. “A probation violation report was filed on Friday recommending revocation of her probation. A warrant for her arrest was subsequently issued that remains outstanding.”

Lewis, now 17, was a 15-year-old runaway and a victim of human trafficking who was initially charged with first-degree murder after she stabbed her accused rapist to death.

After pleading guilty to involuntary manslaughter and willful injury, Lewis was sentenced by an Iowa court to five years of closely supervised probation and ordered to pay $150,000 restitution to the man’s family. While Lewis managed to avoid up to 10 years in prison, Polk County District Judge David M. Porter warned that any violation of her probation could result in having to serve a 20-year prison sentence.

In September, a GoFundMe campaign started for Lewis raised more than $562,000, with donations pouring in from over 15,000 people.

The GoFundMe was started by Lewis’ former math teacher, Leland Schipper, who stated on the page that the funds will be used to pay off her restitution to Brooks’ family and the state, “Remove financial barriers for Pieper in pursuing college/university or starting her own business,” and to “Give Pieper the financial capacity to explore ways to help other young victims of sex crimes.”