Rohan, who was poisoned by his parents Dipankar Samaddar and Subhra (above) before they committed suicide. Pictures by Amit Datta

A debt-ridden realtor and his wife killed their only child by giving him a poisoned glass of milk before committing suicide in their Naktala flat.

The bodies were found around 9.30am on Wednesday when neighbours and policemen broke open the door of the ground-floor flat. Dipankar Samaddar, 42, was hanging from the ceiling of the dining room. A suicide note was lying on the table.

In one of the two bedrooms, Dipankar’s wife Subhra was hanging from the ceiling. Their 11-year-old son Rohan was lying on the bed, his mouth covered in froth and blood.

South 24-Parganas police superintendent Praveen Kumar said the couple killed the Class VI student before committing suicide.

“The boy was given a glass of milk laced with poison. The liquid had turned bluish when we entered the room. The post-mortem will help us determine the time of the murder and the suicides,” said Kumar.

According to an officer of Jadavpur police station, the suicide note was handwritten on both sides of a small sheet of paper. “Jader haath dhore ami namlam… tarai amake shesh kore dilo (Those who helped me start have now finished me),” wrote the realtor.

He held some business associates responsible for the losses he had suffered. The associates, who were referred to only by their nicknames, are yet to be identified.

Dipankar also ran a cement shop in the locality. One of the workers there, Chandan, first suspected something was amiss when his repeated knocks on the door of the Samaddars’ flat went unanswered on Wednesday morning.

“After Chandan alerted us, we went to the flat and knocked several times. When we noticed that the air-conditioner was running, we peeped in and saw Dipankar hanging,” said Bhaskar Bakshi, who lives next door.

Subhra’s brother Samir Samaddar, who lives in the same area, had no clue that the couple were going through a hard time. “They came over to my place on Jamai Sashthi (Monday). Nothing seemed out of place. Subhra and Rohan would often drop by for a couple of hours,” he said.

An officer investigating the case said Dipankar had ventured into the construction business — and started supporting Left Front-partner RSP actively — about three years ago.

“He suffered massive losses recently. He had built a small bridge in Budge Budge and was working on another project in Joka. He had also started work on a highrise in Naktala but could not finish it,” said the investigator.

The youngest of six siblings, Dipankar was not close to his brothers. “He used to stay with us but moved out 13 years ago after marrying Subhra. He rented a room in a relative’s house and stayed there with his family for eight years before buying the flat,” said Dipankar’s brother and neighbour Nitai.

“We have no idea about Dipankar’s family life or the state of his business. He did not visit us after moving out,” added Nitai.