RAWALPINDI: Two labourers died of asphyxiation on Wednesday night after apparently inhaling poisonous gas emitting from a coal stove they had been using for heating in an under-construction house in Rawat. According to police sources, a third labourer was found unconscious in the room and was shifted to the hospital where his condition was stated to be critical. Muhammad Fiaz and Ghulam Shabir, who belonged to Kot Addu, had been working at an under-construction house when they slept on Wednesday night after putting a coal stove on. The three labourers were found fainting on Thursday morning. Sources said when their colleagues opened the door, they found the room filled with poisonous gas.