RAPID CITY - Authorities have identified a Spearfish man who died while fishing at Pactola Lake in southwestern South Dakota, but they still don't know how he died.

Thirty-nine-year-old Daniel Eatman died Wednesday afternoon. Authorities say he was fishing with a relative when he collapsed and fell into the water. He was pronounced dead en route to a Rapid City hospital.

Officials say preliminary results of an autopsy were inconclusive and more testing is planned.

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