KANKAKEE, Ill. (AP) _ A dialysis patient shot a nurse before killing himself today, apparently angry over being denied something to drink.

The man was undergoing dialysis, a treatment to remove waste products from the blood of patients whose kidneys have failed, when he asked for a drink. The nurse refused _ standard procedure during dialysis _ and the man began arguing about it, St. Mary's Hospital spokesman Paul Tutt said.

About an hour after being discharged, the man returned to the nurse's office and shot her before shooting himself in the head, Tutt said.

Authorities said it was not known how many shots were fired.

The nurse was being treated for a single gunshot wound, but her condition was not known, Tutt said.

St. Mary's is one of two hospitals that were swamped with injured patients from last week's Amtrak crash in nearby Bourbonnais that left 11 people dead.

``I can't believe this is happening,'' said hospital spokeswoman Becky Wilder.