Ganesh Sikdar (60) and his wife Pushpa Sikdar (54) were asleep early yesterday when their first-floor home was set on fire by spreading kerosene, DC DD Barrackpore Kalyan Mukherjee said.
The couple's daughter, Rinki Sikdar, in her police complaint, alleged that the sister-in-law, Jharna, locked the door of her parents' room from outside and set it ablaze by dousing kerosene.
Jharna, who has been arrested, stays in the ground floor of the house and her husband Pradyut works in Middle East, the police said.
The daughter told the police that her parents were against selling their house to a real estate developer and that was the cause of dispute with Jharna and her husband.
Rinki was sleeping in a ground-floor room at the two-storey house, the police said.
A local court remanded Jharna in seven days' police custody when she was produced there later in the day, sources said.