ST. PAUL — A serial burglar has pleaded guilty to killing an elderly woman after breaking into her St. Paul home three decades ago.

Sixty-year-old Michael Withers entered the plea to second-degree murder without intent Friday in Ramsey County District Court and could be sentenced to 20 years in prison.

Eighty-one-year-old Lillian Kuller fought with her intruder before he strangled her in 1987. Authorities had done DNA tests on evidence, but it wasn’t until Y-chromosome profile tests on some evidence, including Kuller’s fingernail clippings, were done that investigators came up with a match to Withers. Those results were received in March 2017.

Withers lived about a mile from Kuller’s house at the time of the homicide. He’s scheduled for sentencing Oct. 30.