LOS ANGELES (AP)  — Prosecutors say they believe a 14-year-old Los Angeles-area boy charged with killing his father opened fire as part of a dispute over grades.

The boy, whose name wasn’t released because he is a minor, faces one count of murder with an allegation that he used a firearm to shoot his father, Immigration and Customs Enforcement agent Myron Chisem. Authorities say the boy used his father’s service weapon in Wednesday’s shooting in Carson.

Authorities said the boy then called 911, telling a dispatcher his father had been shot. The weapon was found in the front yard but it’s not known how the teen might have gotten it.

Prosecutors said they will seek to have the teen tried as an adult when he appears Monday in Juvenile Court. He remains in custody.

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