The incident took place yesterday when the two workers Akshay and Rakesh fell in the septic tank of Max hospital while cleaning it, their supervisor Manmohan also got inside the tank to help them out.
The people standing around raised an alarm following which police was informed and a fire brigade was called. However, by the time the fire brigade took them out, they were already dead, police said.
A case of negligence has been registered against the coordinator of Max hospital and engineers and contractors handling that sewage treatment plant, police said.