A 21-year-old Montana man on Wednesday was sentenced to almost 42 years in prison after kidnapping, raping and leaving a 4-year-old girl for dead on the Fort Peck Indian Reservation.

John William Lieba II was accused of chasing down the 4-year-old girl at night in a park last year, raping and strangling her, and then leaving her for dead in an abandoned pickup truck where she was not found for two days. The rape left her with an incurable sexually transmitted disease.

“Lieba, through his actions, forced every parent in Montana to confront their worst nightmare," Assistant U.S. Attorney Ryan G. Weldon stated in a sentencing memo filed in federal court.

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When found by a sheriff’s deputy, the girl was alive but had bruises and burst blood vessels on her head and neck, indicating that Lieba had attempted to strangle her.

The sexual assault not only injured the girl but also infected her with the incurable STD, said Dr. Cynthia Brewer of the Billings Clinic, who examined the girl and testified at Lieba’s April trial, The Sun reported.

A friend of the victim testified at the trial that she saw Lieba take the young girl after they’d been playing in a park on the reservation, according to court records.

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When interviewed, Lieba initially denied knowing of the kidnapping and never showed contrition or remorse for his actions, authorities said.

A jury convicted him on counts of kidnapping a minor, aggravated sexual abuse and assault resulting in serious bodily injury on a minor.

Defense attorneys said Lieba had stopped taking his anti-psychotic medication prior to the kidnapping and could not remember the events.

Judge Brian Morris sentenced Lieba, in U.S. District Court in Great Falls, to 500 months in prison on each count, to be served concurrently, five years of supervised release, and a $300 special assessment, according to a release from the Department of Justice.

The Associated Press contributed to this report.