(AP) — An 81-year-old Lincoln man accused of killing his wife, who had advanced Alzheimer’s disease, has died at a hospital.

John Kotopka had pleaded not guilty to first-degree murder and was being held at the Lancaster County Department of Corrections awaiting trial.

A release from the jail said Kotopka died Thursday.

The news release said the cause of death has not been determined, but Kotopka had a chronic medical condition.

Police said Kotopka shot 78-year-old Janet Kotopka at their home on June 20.

Janet Kotopka required constant monitoring because of health problems.