METROPOLIS, Ill. (AP) - Prosecutors in southern Illinois have dropped charges against a man who’d been accused of killing his 15-month-old son.

The (Carbondale) Southern Illinoisan reports that special prosecutor David Rands cleared 35-year-old John Pruett of Metropolis. He disclosed in a court motion that medical experts in the largely circumstantial case concluded Pruett could not be responsible.

Pruett had been charged with first-degree murder.

Illinois State Police had said Jackson Pruett was taken unresponsive to a Metropolis hospital in April 2010. The toddler died two days later at a St. Louis hospital.

Pruett was indicted last November and was arrested the next day.

Authorities say the boy died of a head injury.

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