EL DORADO COUNTY (CBS13) – The Benicia teen accused of killing his father, his father’s fiancée and the couple’s 8-year-old son in 2015 has been convicted of murder, Sacramento CBS affiliate CBS 13 reports.

Back in September 2015, the remains of the Adam Buchanan, Molly McAfee and their son Gavin were found in a burned-out cabin in the Greenwood area of El Dorado County. Nolen Buchanan, then 16, was later arrested for the deaths.

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Prosecutors said Nolen shot and killed the three before dousing the cabin in gasoline and lighting the place on fire.

During the trial, prosecutors argued that Nolen planned to kill the three before leaving for the cabin that weekend.

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Nolen testified during the trial that his father Adam killed Molly and Gavin. Nolen argued that he wrestled the gun away from him and then shot him in self-defense. However, the district attorney’s office countered that the story was “forensically impossible.”

On Wednesday, a jury found Nolen guilty on three counts of first-degree murder.

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Nolen now faces sentencing at a later date.