OKLAHOMA CITY (AP) - An Oklahoma judge has ruled a doctor diagnosed with bipolar disorder who is accused of fatally stabbing his 9-year-old son is competent to stand trial on a first-degree murder charge.

The judge's Tuesday ruling didn't address whether Dr. Stephen Paul Wolf was legally insane when he allegedly attacked his son, Tommy.

Wolf was arrested Nov. 16 after a police officer found him in the family's suburban Oklahoma City home, hovering over his son, who had two knives stuck in his chest. The officer heard Wolf say: "You know he's got the devil in him."

A state psychologist reported Wolf understands the charge against him. Wolf was diagnosed before his arrest with bipolar disorder and told the judge he is taking a variety of prescription drugs.

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