Arguments got underway Tuesday morning in the trial of a 22-year-old soldier accused of murdering the mother of his under-aged girlfriend.

Army Spc. Caleb Barnes stands accused in Lehigh County court in the March 2015 death of Cheryl Silvonek, a Jim Thorpe native who lived in Upper Macungie Township.

Tuesday morning, prosecutors laid out their case against Barnes in opening arguments.

An assistant district attorney said that Barnes admitted to killing Silvonek during his first interview with police, and that they planned to show through text messages and testimony that the murder was pre-meditated.

The prosecution said that Barnes and Silvonek's daughter Jamie, who was 14 at the time of the killing, planned to kill her because she became aware of their sexual relationship.

Jurors heard from detectives who discovered Cheryl Silvonek's body in a shallow grave along Hassendahl Road in South Whitehall Township on the morning of the alleged murder. They also heard from the resident who discovered the vehicle while walking his dogs at approximately 3:30 that morning.

Silvonek's vehicle was discovered abandoned in some brush at the bank of a pond on Applewood Drive, about a mile from where the body was discovered.

Prior to the lunch break, a Lehigh County detective was recalling the opening hours of the investigation, how the vehicle led them to the Silvonek home, where they discovered Barnes and Jamie Silvonek in bed naked, and their subsequent interviews.

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