Credit: New Braunfels Police Department

Authorities are investigating what led a Texas teen to fatally shoot his own sister.

According to reports, New Braunfels police officers arrested 17-year-old Zachary Barrera Sunday after his sister, 16-year-old Gabrielle Barrera, was found dead at a home Saturday night. Authorities said Gabrielle suffered a gunshot wound and died at the scene.

Detectives determined the boy fired the handgun that killed his sister, but they are now trying to determine a motive.

Zachary Barrera has been charged with first-degree murder and is in custody at Comal County Jail. His bond has been set at $250,000.

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