CRANBERRY TOWNSHIP, Pa. -- State police said 75-year-old Robert Riddle shot and killed his wife before turning the gun on himself Friday morning inside UPMC Northwest Regional Hospital in Cranberry Township, Venango County.

Riddle, who was apparently distraught over the failing health of his wife, arrived at UPMC with a concealed gun and shot 74-year-old Shirley Riddle once, just before 9 a.m.

A note was discovered inside of the Riddle's Oil City home. He reportedly wrote that he could no longer permit his wife's suffering.

No other patients, visitors or staff members were injured in the shooting.

Except for a portion of the unit where the incident occurred, all inpatient and outpatient services continued without interruption.

The services of UPMC Northwest's employee assistance program are being provided to staff members as needed to aid them in dealing with the incident.

"This is a very tragic situation that greatly saddens us, and we extend our sincere sympathy to the family," said UPMC Northwest President Neil Todhunter. "Although this was an extremely unfortunate incident, we are especially grateful that no one else was injured."