Four people succumbed to their burn wounds on Monday due to an explosion earlier caused by gas leakage at a building on Burns Road. The unfortunate incident took place on May 15 due to gas leakage in a faulty air conditioner, which wounded seven people, according to Bomb Disposal Squad. At the time of the explosion, the true cause behind the incident could not be ascertained. It was later found to be a gas blast. The wounded were shifted to a nearby hospital, however, four of them succumbed to their wounds later on. According to the hospital administration, the deceased had 80 to 90% burn wounds. Currently, three people are still under treatment, said the administration.