Eleven persons, including a woman and two children, were killed while two others suffered burn injuries in a cylinder blast at a perfume factory in Lahore early on Tuesday.According to Rescue 1122 spokesman, fire erupted in the factory situated in Imamia Colony in Shahdara which led to explosion of gas cylinder causing the building to collapse. He said the explosion was so powerful that it damaged nearby homes as well. Hospital officials said one of the injured was in critical condition. Witnesses said they heard a huge blast and said the factory went up in flames within minutes. TV footage showed firefighters dousing the blaze as relatives of the labourers trapped inside wailed and cried for help. Later, authorities said the rescue operation was complete and there was no one left alive in the building. Due to intensity of the blaze in a congested area, the residents were earlier advised to move to safer areas during the rescue operation.Six of the 11 dead have been identified as Zahid Fazal (60), Rasheeda (55), Musa (9), Areeba (7), Naveed (14) and factory owner Abid (45). Zahid Majeed (30) and Junaid Akram (21) sustained injuries in the incident. Gas cylinder explosions and other similar accidents are common in the country, mainly due to insufficient enforcement of safety standards and poor infrastructure.