All four died due to suffocation after inhaling poisonous gas.
Four people, including two migrant labourers, died on Tuesday after inhaling toxic gas while laying pipes in a septic tank in Bahadurgarh in Haryana's Jhajjar district, police said.
The incident happened in Jakhoda village when a mason and some labourers were repairing the tank.
"When the mason fell unconscious, another person went inside to check on him, but did not come out. Two labourers -- one from UP and another from MP -- who tried to help also fell unconscious," Jasvir, SHO of Aasoda police station in Bahadurgarh, said over the phone.
All four died due to suffocation after inhaling poisonous gas, he added.
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