A Rockford man has pleaded guilty but mentally ill in the beating death of a 75-year-old woman.

A state prosecutor said Thursday that 44-year-old Reed Catalano entered the plea to first-degree murder and felony unlawful restraint in Winnebago County court.

Catalano admitted to killing Elizabeth Kincade in July 2013. Kincade was fond in the basement of her residence and an autopsy showed she had been beaten and was dead for about 24 hours before she was found.

Authorities say Catalano lived with Kincade but wasn't related to her.

First-degree murder carries a sentence of 20 to 60 years in prison while unlawful restraint is punishable by an extended term sentence of one to six years. Catalano is set to be sentenced in January.