The Texas City disaster was an industrial accident that occurred April 16, 1947, in the Port of Texas City. It was the deadliest industrial accident in U.S. history, and one of the largest non-nuclear explosions. Originating with a mid-morning fire on board the French-registered vessel SS Grandcamp (docked in the port), its cargo of approximately 2,300 tons (approximately 2,100 metric tons) of ammonium nitrate detonated, with the initial blast and subsequent chain-reaction of further fires and explosions in other ships and nearby oil-storage facilities killing at least 581 people, including all but one member of the Texas City fire department.