Two siblings died after inhaling toxic gas in a septic tank at Uttorshom village in Kaliganj Upazila of Gazipur on Sunday.The deceased were identified as Mohsin Mia, 42, President of Tumulia Union Jubo Dal, and his brother Masum Mia, 30.Locals said, Mohsin and Masum lost consciousness after inhaling toxic gas when they went inside the septic tank at their house to clean it.Later, the duo were rescued by local people and rushed to Kaliganj Upazila Health Complex where on-duty doctors referred them to Dhaka for better treatment.They succumbed to their injuries on the way to Dhaka.