Cops randomly checking vehicles near Science City early on Friday found a woman’s body in a sack stuffed with vegetables in a taxi’s boot.

The taxi had two passengers, a man and a woman, apart from the driver when a police patrol from Pragati Maidan police station stopped the vehicle.

The two have been identified as Malina Mandal, the prime accused, and Ajay Rang, a family friend, and the dead woman, Suja Mani Gayen, the police said.

They apparently told cops they had killed the woman and that they were on their way to dispose of the body.

Preliminary investigations showed Gayen was the mother-in-law of Mandal’s daughter, an officer of Pragati Maidan police station said. “It appears Mandal wanted to eliminate Gayen... she has said Gayen used to torture her daughter.”

Mandal has said in her statement that she and her husband had thrashed Gayen, 60, with a bamboo stick before strangling her to death, the police said.

Mandal, a resident of Arupota village in Chowbaga, is a vegetable vendor. She had chosen to hide the body in a sackful of vegetables, the police said.

Gayen, a resident of Kabardanga in the Haridevpur area, was brought to Mandal’s home on some pretext.

Mandal has claimed the motive behind the murder was the deceased woman’s torture against her daughter but cops are still to verify the claim.

“We will question Mandal’s daughter to check the veracity of her mother’s claims. Even if the claims turn out to be true, it does not justify the killing,” an officer said.

Mandal, her brother Basu Mandal, and Rang were arrested on charges of murder later on Friday.

Her husband is still to be arrested. Investigations are on to find out if the taxi driver was involved in the crime, the police said.