NEW DELHI, May 4 -- "Their last words were that the 'door is jammed'" said Sonali Jain, with tears rolling out her eyes. Her parents-in-law, brother-in-law, his wife, and their one-year-old child are among the nine people who died in the fire that caught residents of a residential building in east Delhi's Vivek Vihar by surprise.

The fire, which is suspected to have started after a short-circuit in the AC on the second floor, quickly engulfed the upper floors, which, along with the structure and design of the building left them with no way to escape.

On the third floor, the family made frantic calls for help as the fire spread. "They couldn't open the door," Sonali said. After the blaze was doused around 8 am, the charred bodies of Arvi...