At least eight persons, including three infants, were killed on Thursday when a massive blaze engulfed a medical store in Mumbai's Andheri suburb, an official said.Three others, including a fireman battling the blaze were injured, said an official of BMC Disaster Control.The cause of the huge fire is still unknown but it was so intense that it resulted in eight deaths in a matter of an hour. The victims were from two families living above the store.While six of them died due to suffocation by the emanating toxic fumes, two sustained severe burns, said the Brihanmumbai Municipal Corporation (BMC) Disaster control.The injured were rushed to the nearby Cooper Hospital in Juhu and two were discharged after treatment while one woman, Sofia Khan, 28, is undergoing treatment for upto 40 per cent burns.The pharmacy is situated in a chawl on the Juhu Gully in Andheri west and went up in flames around 6.15 a.m.The fire was contained within an hour, the official added.