An elderly childless couple who owned a two-storey house, along with relatives, on a corner plot in a south Calcutta neighbourhood were found murdered on Tuesday morning.

The body of Swapna Mukherjee, 65, was lying on the landing leading to the first floor of 50A Ashoke Avenue, near Netaji Nagar police station. Husband Dilip, 75, was on a bed with his legs hanging.

“There were marks of violence on the woman’s body, while the man was gagged and then smothered with a pillow,” a police officer aware of the findings of a preliminary investigation said.

The police suspect someone the couple knew had pressed the doorbell around 10pm and killed Swapna before attacking Mukherjee, who was sitting on the bed.

The eight-cottah corner plot on which the house stands is surrounded by a number of newly built and under-construction apartment blocks.

The murdered couple. Collected from a family album

The police said the couple were looked after by a help who would come daily around 11am. She would leave around 8pm, after which she works as a nurse elsewhere.

“They were fine when I left last night. I was shocked when I came to know what had happened to them when I turned up for work today. A promoter had been making calls. I answered two such calls and told him clearly that the owners did not want to sell the property,” the woman said on Tuesday morning.

An officer of the homicide department said Dilip, who till a few years ago was involved in water treatment of rooftops, had withdrawn Rs 50,000 from the bank a few days ago.

“He was accompanied to the bank and back home by one of their tenants.... Of the 11 cupboards in the house, 10 were found ajar with the keys hanging from the keyholes,” the officer said.

The cupboard that was not opened contained Rs 2.5 lakh, gold ornaments and fixed deposit documents for Rs 30 lakh.

“The help said she had kept Rs 20,000 with the couple, who she said were like her guardians. She said the money was missing,” the officer said.

“A mobile phone was missing, too. An investigation revealed that the SIM card had been removed from the phone around 1.5km away from the house.”

The bodies of the Mukherjees were first spotted around 8.30am by a youth who would accompany Dilip during his morning and evening walk. “The door of the house was open when the youth arrived. He alerted a neighbour immediately after seeing the bodies,” the officer said.

The Mukherjees had three tenants — a man who lives on the ground floor and runs a small paint store, a woman who runs a grocery shop on the ground floor and another man who runs a clothes-ironing unit on the ground floor.

An elderly neighbour said she had last seen Dilip two days ago.

“He was walking with the youth. He and his wife would often sit on the balcony,” the neighbour said.

The lights of the house were on when the police arrived, suggesting that the couple were killed at night.

Of the three parathas the maid had prepared for the couple, two and a half were left. The utensils that were possibly used for dinner were lying unwashed in the sink.

“Mukherjee would eat dinner first. His wife would clean the utensils and then eat. It appears she did not get the chance to eat dinner,” a senior officer said.

The interior of the house was recently painted and several construction tools were found inside.

“We came to know about the incident from the police in the morning,” said Dilip’s niece Nilanjana Bose, who came to the house with other family members.