The labourers were from Bihar and their identities were being ascertained. (Representational)
Four labourers from Bihar died of asphyxiation after entering a septic tank at a dyeing unit in Surat's Palsana locality, the police have said.
The incident took place at a factory on Palsana-Katodara road on Tuesday evening.
Two labourers fell unconscious while cleaning the septic tank, and two others who tried to rescue them too fainted, said an official of Pansala police station.
All four were taken out of the tank and rushed to the hospital where doctors declared them dead, the police official said.
The labourers were from Bihar and their identities were being ascertained, he added.
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