Mumbai: Nine persons, including three infants, were killed when a major fire engulfed a medical store in suburban Andheri here early on Thursday, an official said. Another two persons, including a fireman battling the blaze, have been injured, said an official of BMC Disaster Control. The cause of the fire - in Wafa Medical & General Stores - was unclear but it was so intense that it caught unawares all the victims from two families living above the pharmacy store. While six persons died due to suffocation caused by the toxic fumes, three sustained severe burns and succumbed, said the official. The two injured were rushed to the nearby Cooper Hospital at Juhu and discharged after treatment. The pharmacy is situated in a chawl on the busy Juhu Gully in Andheri West and went up in flames around 6.15 a.m. The devastating conflagration, prima facie believed to be caused by a short-circuit in the wiring system was brought under control within an hour by the fire brigade, the official said. Those dead were identified as Husaif Khan (eight months), Tubah Khan and Altamas Khan (both three months old), Shagun N. Khan, 52, Siddik Khan, 35, Rabil Khan, 28, Umi Hami Khan, 5, and Aliza Khan, 4, besides 28-year old Sofia Khan who succumbed in Kasturba Hospital. A fireman who sustained burns, Avinash K. Singhankar, 45, was given medical treatment, the Disaster Control said. According to investigators, the dawn blaze occurred in the ground floor pharmacy quickly spread to the two upper floors of the chawl, engulfing the sleeping victims. It is also suspected that a small internal staircase connecting the two floors trapped the residents of the two families and led to the nine fatalities in such a short time.