A contractor's negligence and the alleged indifference of the housing society that hired them has cost three workers their lives. The trio, migrants from Haryana, died when they suffocated in a sewage tank they had to clean at the society in Dhokali, Thane, on Thursday. Kapurbawdi police, who registered a case against the contractor and arrested him, said the workers had not followed basic rules and did not have safety equipment.

The trio, aged between 20 and 24, were hired with five other workers to clean the tanks in a sewage treatment plant (STP) operated in the posh Pride Presidency at Thane. The STP was constructed by the builder and is being operated by the society from March 2012. It is learnt that while the workers were not provided safety equipment, the contractor, Dilip Patil, also chose to make them work from afternoon into the night. The dead were identified as Amit Puhal, 20, Aman Badal, 21, and Ajay Bumbak, 24. The other workers, also from Haryana, are Vijendra Hatwal, 25, Manjit Vaidya, 25, Jasbir Puhal, 24, Rummer Puhal, 30 and Ajay Puhal, 21. Amit had married recently.