A last defendant has pleaded guilty in connection with the 2001 explosion at a fireworks factory south of St. Louis that injured three workers. Russell Nickel of Columbus, Montana pleaded guilty to lying to the Occupational Safety and Health Administration during OSHA’s investigation of the explosion at the Pyro Products factory in Dittmer in June of 2001. The explosion occurred in a work building where Pyro manufactured products for Next F/X Incorporated. Nickel told OSHA he had nothing to do with Next F/X. Missouri incorporation documents list Nickel as Vice President of Next F/X. Co-defedants Ronald Robert Walker and his wife, Kim Walker, also of Columbus, Montana, pleaded guilty earlier to conspiracy to illegally transport hazardous wastes and illegal storage of explosives. The two companies involved have also pleaded guilty to related charges.