She was identified as Anita Singh (25).
The incident took place on February 7, said Additional Superintendent of Police Raisingh Narvaria.
According to her mother-in-law, as the girl started crying, seeking to be suckled, an angry Anita took her inside the house. "Immediately the baby's screams stopped, and then Anita walked out hurriedly, causing her mother-in-law to suspect that something was wrong," Narvaria said.
The mother-in-law called neighbours, who went into the house and saw to their horror that the little girl was lying in a pool of blood, her throat slit with a sickle.
Further probe is on, he added.