KOLKATA: In yet another twist in the New Town child murder case, police now say that the killing was an occult sacrifice and not a spur-of-the-moment crime as the prime accused — granny Aarti Naskar and aunt Kavita Naskar — had made it out to be.

Police are surprised by how long Aarti and Kavita managed to hold out under relentless interrogation. The murder was committed on Mahalaya, discovered two days later, on October 14, and it was not until October 24 that the duo cracked. They had all along tried to mislead the investigation. Even after confessing on October 17, the 63-year-old granny and Kavita stuck to a cooked-up story to dodge harsher charges for a planned murder, say police. “They are still trying to hoodwink us. You can imagine their resolve,” said an investigator.

Macabre as it may sound, little Preeti Naskar was killed just 2km from the New Town IT hub because Aarti and Kavita were told by a tantric that if the child were sacrificed on the “auspicious Mahendra jog” — Amavasya on Mahalaya — they would gain “unheard of wealth” and a long life, say police. Kavita is a graduate and took pride in being the most educated in the family.

On Saturday, in her second ‘confession’, Aarti told police that she had a dream of Tara Ma a couple of weeks ago and “followed the directions” after consulting a tantric. A week before Mahalaya, Aarti and Kavita hatched the murder plan, said an officer.

A week ago, the duo had claimed that Aarti chopped off Preti’s fingers in a fit of rage after the child disrupted her Mahalaya Puja and then Aarti choked her to death. But on Saturday, Kavita admitted that she lured Preeti to the prayer room, said an officer. Around 11am, Aarti brought a knife from the kitchen. “The child was forced to put her left hand on the floor near the prayer room. They stuffed a gag into her mouth and cut off her index and little fingers. When she fell unconscious from the shock and blood loss, the two women asphyxiated her. Kavita stuffed a red cloth, used in pujas, down Preeti's throat to choke her to death,” said an officer on Saturday.

The fingers were washed in a bucket in the bathroom and “offered” in an occult ritual. The knife was washed carefully and replaced in the kitchen (it was seized on Saturday). And the body was hidden behind the deities and the fridge. A few hours later, the women joined the rest of the extended family in the search for Preeti and even named their tenant as a suspect to divert attention. In the dead of night, at 1am, they returned to the house, put Preeti’s body in a sack and left it in the terrace. The next day, they again joined the search.

Investigators had all along suspected Kavita and Aarti because they were the only ones at home when Preeti went missing. But the motive was unclear. Investigation seemed stuck at a dead end when forensic experts found a few tiny spots of blood on Kavita’s saree even after she had washed it. That proved to be clinching evidence, said an officer. Six to seven tantrics have been recalled for another round of questioning to identify who had “advised” Aarati and Kavita about the human sacrifice.