A couple and their five-year-old son died in Haryana's Faridabad due to suspected carbon monoxide poisoning after they went to sleep in a room kept warm by burning coal.
The victims were residents of Bihar and living in a rented accommodation in Faridabad, police said.
"The man and the woman, aged around 24 years, and their minor child, inhaled some poisonous gas in their sleep last night from the burning coal kept in a container," Station House Officer, Sector 58, Anil Kumar said.
They lived in a small room that had no window, he said, adding that the man worked at a nearby factory.
"The burning coal had been kept in the room by the family to keep themselves warm, but they did not realise that the room was without ventilation and would be filled by poisonous gases. The three died in their sleep," Mr Kumar said.
Their landlord got suspicious when no one from the family came out of the house. He with the help of some of his neighbours broke open the door and found the three lying motionless, the SHO said.
Mr Kumar said that after being informed, a police team reached the site. The couple's family members have been informed, he said.
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