A 15-year-old boy shot and killed his brother after they fought for the affection of the same girl, police claimed in court documents Wednesday.

Dakota Thornton faces charges including first-degree murder. He'll be tried as an adult, Fox 43 reports.

Police said early Wednesday morning, they confronted the Dauphin County teen over the death of 18-year-old Dominick Thornton when Dakota admitted, "I shot my brother."

"It's a tragic event and one that was entirely preventable," Dauphin County District Attorney Ed Marsico reacted.

Police did not name the girlfriend.

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