A man welding on a trailer at Bridgeport Tank Trucks in Bridgeport was killed in an explosion just before 8 Wednesday morning. Bridgeport Police Chief Randy Singleton said the 50-year-old male, whose identity is being withheld pending the notification of next of kin, was working just outside the shop at the business when the explosion occurred. Singleton said it is very early in the investigation, but it appears that residual fumes in the tank ignited during the welding causing the explosion which knocked the victim back several feet. The blast caused damage to two other nearby vehicles, but no other employees were injured, and it appeared the shop did not sustain damage. The debris field stretched for a 100 foot by 100 foot area, Singleton said. In addition to Bridgeport police, the Bridgeport Fire Department, Wise County EMS and Wise County Fire Marshal Chuck Beard responded to the scene.