Gunfire near power plant deemed 'unusual,' lowest NRC classification SPRING CITY, Tenn., April 21 (UPI) -- A security officer patrolling near a Tennessee nuclear power plant Sunday exchanged gunfire with an individual, Nuclear Regulatory Commission officials said. The NRC Region II staff began monitoring the Watts Bar plant near Spring City, approximately 60 miles southwest of Knoxville, after the Tennessee Valley Authority, which operated the plant, notified the NRC of the incident, the Knoxville News Sentinel reported. The incident occurred about a quarter mile outside the plant's protected area, the news sources said, adding the officer was not injured. Watts Bar plant officials declared an unusual event, the lowest of the NRC's four emergency classifications.