The fire broke out due to a cylinder blast in the slum.

Three children of a family, including a six-month-old boy, died and another was severely injured in a fire that broke out at a slum cluster in northeast Delhi's New Usmanpur area, police said today.Police suspect that the fire was caused by a short circuit followed by three cooking gas cylinders explosions.The people who died have been identified as Reena (10), Meena (7), daughters of one Kallu Ram, and his six-month-old son, Mubarak.Their neighbour's son Shakhuddin also got trapped inside a burning shanty and he is now admitted in a hospital with 60 per cent burn injuries, said police.The fire broke out around 11.30 pm last night, following which eight fire tenders were rushed to the spot.More than a dozen shanties were gutted by the fire and it took the firefighters around three hours to douse the flames and finish the cooling operation, said an official at Delhi Fire Services.The children were trapped in their shanties and, except one, the others could not be saved despite the launch of an immediate joint rescue operation by police and fire officials, they police.Two buffaloes also died in the fire and the injured child Shakhuddin's father Allah Rakha also suffered burn injuries while trying to save the children, police said.