A team of police rushed to a rented house on Klong Wan-Wa Ko road in Muang district after Pol Capt Amorn Phetduang, the duty officer at Klong Wan police station, was informed of the incident at about 8am by Tai, a Myanmar migrant worker.
They broke into the house and found it full of smoke. They found five people lying in the room.
A Myanmar woman, identified later as Yapato, 22, and her three-day old baby son were dead. A 35-year-old woman, a 15-year-old girl and a six-year-old boy were found lying unconscious. All were quickly moved from the house.
The smoke was found to have come from three burning logs of wood.
It was believed Mrs Yapato was lying by the fire in a traditional way of helping a mother to recover after a childbirth and the others, including her three-day old son, were asleep in the room which had no ventilation
Tai, Mrs Yapato's husband who worked the night shift on a fishing boat, found the house covered with smoke when he returned home in the morning.