Three persons were asphyxiated while cleaning a septic tank in Ponthur near Sriperumbudur on Wednesday.
The incident took place around 2.30 p.m. when two workers, Murugesan, 30, and Mari alias Ajith, 30, both from Pattabiram, entered the tank at a hotel on Oragadam Road.
Murugesan slipped and fell into the tank after inhaling the fumes, followed by Mari.
Ravi, 40, of Somangalam, who was supervising the work on behalf of the hotel management, tried to rescue them, but also fell into the tank and died.
According to the police, the hotel management had engaged a local septic tank cleaning agency to clear the sewage.
The contractor, Kumar, used to hire people on work order basis to accompany the vehicle fitted with suction facility driven by his employer.
The persons engaged for the work had to help the driver in clearing the sewage from the tank using the suction machine and later enter the tank and clear the sediments. However, on Wednesday, the deceased entered the tank well before the sewage was completely removed using the machine, the police said.
Two detained
The Sriperumbudur police, who have booked a case, have taken two persons, who are in charge of managing the hotel, into their custody for interrogation.
The sewage cleaning service provider is absconding.
