A man pleaded guilty to murder Tuesday, admitting he left his 3-year-old foster son bound up in a closet where he died and then burned his body and threw the remains into the Ohio River.

David Carroll Jr. was sentenced to 15 years to life in prison, with an additional year in prison for his guilty plea to gross abuse of a corpse.

He and his wife, Liz, were charged with causing Marcus Fiesel's death by leaving the developmentally disabled boy wrapped up with a blanket and packing tape in a closet for two days while they went to a weekend family reunion in Kentucky in August.

"We left him there," Carroll told the judge, who asked him to explain what happened in his own words. "And when we came back, he was gone ... he was dead."

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Clermont County Judge Jerry McBride accepted the sentence proposed by prosecutors.

A jury last week convicted Liz Carroll, 30, of murder and six other charges, including involuntary manslaughter and kidnapping, in the boy's death. She was sentenced by Judge Robert Ringland to a total of 54 years to life in prison.

As part of the deal with David Carroll, prosecutors agreed to drop six charges against him. Carroll, 29, had faced the same seven charges as his wife, plus the eighth charge of gross abuse of a corpse.