SANTA ANA (AP) — A man and woman have pleaded guilty to killing a gambler they followed after he won $10,000 at a Southern California casino.

Orange County prosecutors say Tad Carroll pleaded Friday to first-degree murder. Barbara Ann Hamel pleaded to second-degree murder.

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Authorities say the pair planned to rob winners at the Hawaiian Gardens Casino in September of 2010.

Prosecutors said they followed 55-year-old Chi Bui and confronted him when he stopped his car to drop off a friend at her Santa Ana home.

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Authorities say Carroll knocked down Bui and Hamel drove over his head, killing him instantly.

A third defendant, Michael Ross of Long Beach, pleaded guilty to second-degree murder in September. He was sentenced to 15 years to life in prison.

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