A suspect has been arrested in the Wednesday shooting that left a civilian Army worker dead at Fort Knox in Kentucky, Nashville NBC affiliate WSMV reported Thursday. Police in Portland, Tenn., near the Kentucky border, arrested the man during a routine traffic stop early on Thursday but have not yet released his identity, according to WSMV. The arrest came after a fatal shooting — which a spokesman for the independent Army investigative agency called "a personal incident and not a random act of violence" — was reported at Fort Knox around 5:40 p.m. local time Wednesday. The victim was an employee of the U.S. Army Human Resources Command and was pronounced dead at the hospital, according to a statement from the Army base. On Wednesday, police had said they were searching for a person they described as a 5-foot, 9-inch black male believed to have been riding a black Yamaha motorcycle. The base had been locked down briefly Wednesday after the shooting.