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.

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.

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

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