FREMONT (CBS/AP) — Investigators say a Fremont father attacking his adult son with a nail-studded baseball bat was shot to death by an older brother.

Fremont police say the shooting death of 48-year-old David Weatherton was a case of self-defense and the older son was released after questioning.

Weatherton was attacking his 25-year-old son last week with a bat studded with nails when his 27-year-old son intervened.

When Weatherton turned to attack his older son, police say the father was shot in the chest and killed.

The younger son wasn’t seriously hurt.

Investigators haven’t disclosed the reason for the baseball bat attack.

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