Officials at Fort Benning say a faulty light fixture in a spare metal building may have contributed to the accidental electrocution of an Arkansas soldier over the weekend. Private Van Ryan Marcum of Prescott was killed during a training exercise Saturday. Officials say the 21-year-old was electrocuted when he touched the outside of the metal structure. Marcum was halfway through his 14-week basic training and planned to attend elite Army Ranger school and eventually serve in Iraq or Afghanistan. Elsie Jackson, a spokesman for the training base, said the Army is conducting a thorough investigation. But Jackson said preliminary findings showed that a light fixture inside the metal building may have been damaged by electrical storms in the area, causing the structure to become unusually conductive.