The City of Durham Fire Department said Friday that the April 10 downtown gas explosion that killed two people and injured 25 was ruled accidental. The department released its Origin and Cause Investigation Report about the deadly explosion Friday afternoon. The report follows a three-month investigation in which more than 25 people were interviewed, and numerous processes, 911 calls, and videotapes were examined and reviewed. The first 911 call reporting a smell of gas occurred at approximately 9:11 a.m. by a woman who was driving in the area. Key investigation findings in the report revealed that the explosion occurred at 115 North Duke Street when “an explosive atmosphere was created when a gas service line was struck during a horizontal boring operation.