TAMPA -- The official autopsy report by the Hillsborough Medical Examiner's Office has confirmed the cause of death of a little girl allegedly left by her mom in the Hillsborough River to be drowning.

Shakayla Denson, 26, of Tampa is charged with first-degree felony murder, aggravated child abuse, and grand theft auto after being accused of leaving her daughter in the river on Aug. 2.

Denson was allegedly seen walking to the edge of the river as she splashed water on herself. A witness says Denson looked out at the water closer to the shore and shouted. She was seen kneeling in the grass after getting out of the water.

MORE: Police: Mother found singing a nursery rhyme after allowing her daughter to drown

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The external examination in the report states that "the body is that of a well-developed and nourished" girl. No physical damage was seen internally or externally by examiners, according to the official autopsy report.

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