FRESNO (CBS/AP) — Authorities say a 16-year-old boy has stabbed and killed a man who attacked his mother at their Central California mobile home.

The Fresno Police Department says the woman’s former boyfriend entered the home on Friday and attacked. He died at a hospital.

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His name hasn’t been released but police say the 46-year-old had recently been released from prison, where he served time for badly beating the woman.

She told police that he came to the home earlier this month with a large hunting knife and threatened her, then returned again Friday.

The boy wasn’t arrested but an investigation continues.

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