Some builders are suspected to be involved in the murder of 77-year-old Namita Guha in her Narkeldanga Main Road home on Thursday afternoon.

Police have found out that the builders had recently visited Guha with a proposal to develop her two-storey house, where she had been living alone since her husband’s death four years ago. Their daughter Suvasree moved out after marriage eight years ago.

“We have spoken to Suvasree about the builders who had approached her mother,” said an officer of the detective department.

“The post-mortem report revealed that she was strangled and then smothered to death between 3pm and 4pm on Thursday,” said city detective chief Jawed Shamim.

According to investigators, the assailants — not more than three — knew the building’s layout well. They only opened the two almirahs that Guha used regularly.

“Some gold jewellery are missing but the gang didn’t take away cash or the gold bangles she was wearing,” said an officer.

Homemaker death: Sunita Jaiswal, a 45-year-old homemaker, was found unconscious in her Ananda Palit Road home on Friday morning. She was taken to SSKM Hospital, where she was pronounced dead.

Her family members claimed that all of them had fallen sick on Thursday night after eating fried rice and paratha prepared by Sunita on Wednesday. Her husband, too, was found unconscious beside her. Police are probing the death.