The well was being deepened and a bulb had been fitted over it to facilitate works last night. Following heavy rain, the bulb fell into the well and they had gone to check it this morning, touching the live wire in the process, DSP P Raju said.
Lieutenant Colonel (retd), Sampath (52), his 70-year-old mother and their servant, Sreerangan (38) suffered electric shock and died, he said.
A case has been registered.