Investigators: Sex Offender Confessed to Slaying 13-year-old Girl TAMPA (WUSF) - (AP) - Investigators say a sex offender accused of killing 13-year-old Sarah Lunde and sinking her body in an abandoned fishing pond has admitted to authorities that he committed the crime.

State attorney's office documents released today in the case against David Onstott also include autopsy results. They show that Sarah died from crushing blows to the head even though investigators earlier said Onstott had confessed to strangling her.

The autopsy found that her killer fractured her skull and broke her jaw before dumping her in an abandoned fishing pond near her home and church in rural southeastern Hillsborough County in April.

Onstott had once dated Sarah's mother. He has been indicted on charges of first-degree murder and attempted sexual battery. He has pleaded innocent and remains in the county jail without bail awaiting trial.

Onstott was convicted of rape in 1995. Prosecutors say they will seek the death penalty.

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