The girl had gone missing from her home on Sunday night, police said. (Representational)
The grandfather of the two-year-old girl, who was found dead in a drain in Khair town, was arrested Wednesday in connection with the murder of the toddler, police said.
Ramesh (65) confessed to the crime after persistent questioning, they said.
The girl had gone missing from her home on Sunday night, and a complaint was lodged by her family the next day, they said.
The postmortem examination indicated that the child died of drowning and there were no visible injury marks.
Senior police official Kalanidhi Naithani said Ramesh, an alcoholic, had run up debts and his children would often confront him on the issue.
On Sunday night, after a heated argument ensued with his children, Ramesh decided to settle scores with his son. He stealthily picked up the sleeping toddler and in a gruesome act of vengeance, plunged her in a drain close to the house.
The incident took place in Khair town about 25 kilometres, Mr Ramesh said.
For the past three days, a team of police officials was camping in Khair. They questioned over 100 people and traced the accused, Mr Ramesh said.
Considering the sensitivity of the case, security was tightened in the area.