<P> Just after 8: 00 am an explosion occurred in the west side of the underground workings . It is possible there were two explosions as survivors stated a smaller explosion preceded the main one, although the official report referred only to one . The cause was probably a build - up of firedamp that was ignited by an electric spark from equipment such as electric bell signalling gear . The initial explosion ignited airborne coal dust, and a shock wave ahead of the explosion raised yet more coal dust, which also combusted . Many victims who were not killed immediately by the explosion and fire died from the effects of afterdamp . The explosive wave travelled up the Lancaster shaft to the surface, destroying the headframe; it killed the winder--the man in charge--and badly wounded his deputy . </P> <P> Edward Shaw, the colliery manager, was on the surface and the remaining shift foremen were still underground and unable to give assistance . He took charge and descended the York shaft, accompanied by overman DR Thomas . The descent was slow, and they had to clear several girders and obstructions before they reached the bottom . They found that the men from the east side of the workings (approximately 450 workers) were unharmed, and their evacuation was ordered . Shaw and Thomas moved to the western side, where they found other men, alive but injured, and arranged for them to travel to the surface . Thomas later reported that the view into the western workings "was exactly like looking into a furnace". </P> <P> Shaw explored what he could of the western workings, before he and some of the survivors began tackling the fire . The water pipes from the surface in the Lancaster shaft were all fractured, and hand - extinguishers were used . Shaw returned to the surface at 9: 30 am to arrange for rescue and fire - fighting teams from neighbouring collieries . From 11: 00 am the specialist mines rescue teams began arriving at the colliery from the Rhymney and Rhondda Valleys, as did Red Cross workers and local ambulance services; a police detachment was sent from Cardiff in a special train . Members of the Inspectorate of Mines were quickly on the scene, and an inspector descended to view the mine the same morning . </P> <P> Lieven recounts how the rescue parties "in their desperation,...were reckless with their lives" in their attempts to find survivors; many were injured in small roof collapses, or suffered the effects of carbon monoxide poisoning . Their endeavours saved lives throughout the remainder of the day and into the night, including a group of 18 men found at around 1: 00 am . They were the last survivors found . A total of 432 miners had died that day--although some bodies were not found until later--and 7 others died later in hospital or at home . A journalist from The Times wrote: "The numbers are truly awful . We talk in awed terms of the decimation of a regiment in a bloody battle, but here a great community engaged in the pursuit of a peaceful vocation is threatened with the loss of at least a quarter of its able bodied manhood". On the surface the townsfolk waited for news; a reporter for The Dundee Courier thought: "the scene at Senghenydd last night was depressing in the extreme . The streets were full of silent throngs of people who moved aimlessly about or stood stolidly at the street corners ." </P>

26 miners killed in south wales pit explosion