The police on Saturday arrested a 25-year-old woman in West Bengal's Nadia district on the charge of smothering her six-month-old son and dumping the body in a septic tank, an officer said.
The incident occurred in Kalyani police station area of the district.
The woman raised an alarm on Friday evening that her son had gone missing, following which the family and neighbours started searching for the baby, the officer said.
The police were informed and they also joined the search. The child's body was found in a nearby septic tank.
During questioning, the police found inconsistencies in the statement of the woman who later admitted that she killed her son.
The motive of the crime is not yet clear, the police said.
Except for the headline, this story has not been edited by The Telegraph Online staff and has been published from a syndicated feed.