A Kentucky nurse accused of killing a 90-year-old World War II veteran with a morphine injection three years ago has pleaded not guilty to murder.

Defense attorney Patrick Nash entered the plea for 32-year-old Maria Kelly Whitt at her arraignment Friday in federal court in Lexington. She is accused of killing Jesse L. Chain with lethal doses of morphine at a veteran's hospital in September 2006.

A Dec. 7 trial date has been set, but Nash says he might need more time to line up medical experts as potential witnesses.

Nash says he doesn't know if Whitt has been questioned by federal investigators about two other deaths at the Veterans Affairs hospital that a federal agent has said were suspicious.

Whitt remained in a western Kentucky jail Friday.