COLORADO SPRINGS, Colo. (AP) — A jury has convicted a Fort Carson soldier of first-degree murder in the death of a 19-year-old woman, whom he got to know over the internet.

The Gazette in Colorado Springs reports that 23-year-old Robert Hull Marko, convicted Thursday, faces a mandatory penalty of life in prison without parole when he’s sentenced Feb. 28. The jury convicted Marko of the rape and murder of Judilianna Lawrence in 2008.

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Prosecutors say Marko raped Lawrence, bound and gagged her, tied her to a tree and slit her throat. Marko’s attorneys argued that their client, who served in Iraq, is mentally ill and suffering from post-traumatic stress disorder.

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Before the trial, Marko pleaded guilty two counts of aggravated sexual assault on a child in a separate incident.

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