A woman has been arrested for allegedly murdering her 3-month-old daughter. Her 13-year-old son has been held for throwing the victim's body in a river, police said.

The investigation began after the 30-year-old unidentified woman from Pune, in the western Indian state of Maharashtra reported to the police that her infant daughter was kidnapped by unidentified suspects on Oct. 22.

Police found out that the woman was separated from her husband and living with her brother. She gave birth to the girl in an alleged extramarital relationship.

According to police, the woman strangled the baby and asked her son to dump the body in the river. She then reported the infant missing, as reported by The Indian Express.

The boy allegedly wrapped his stepsister's body, put it in a burlap sack along with a paving block and threw it from a bridge into the river. The police recovered the infant's body from the river and an autopsy report confirmed that the child died of strangulation.

The woman confessed to the crime during interrogation. Police have registered a case on charges of murder and attempt to destroy evidence.

"The woman confessed that she smothered the baby, while her son dumped the body in the river on Friday," Yonus Shaikh, a senior investigating officer said, The Times of India reported.

The woman has been arrested on the charges while the boy remains detained, police said. The suspect was reportedly irritated with the infant's crying and decided to kill the child, Hindustan Times reported citing RV Varangule, an investigating officer.

Infant
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Last week, a 21-year-old woman in India was arrested for allegedly smothering her newborn daughter to death in a hospital. The woman was reportedly upset that her newborn was a girl and suffocated her baby with a pillow just nine hours after the child was born. The woman confessed to the crime during interrogation.