ROCKFORD, Ill. (AP) — A judge in Rockford has sentenced a 46-year-old man to 25 years in prison for killing his ex-girlfriend.

James Agee walked into the Winnebago County Criminal Justice Center and told officers that he'd killed Denise Davis on Oct. 18, 2010. A short time later, Rockford police officers found the 38-year-old woman unresponsive in her home. She was pronounced dead at a hospital.

A pathologist ruled her death was due to asphyxiation consistent with strangulation.

Judge Gary Pumilia on Thursday sentenced Agee, who'd pleaded guilty to first-degree murder.