Police said that the 84-year-old husband, identified as retired Army doctor Jadunath Mitra, has been admitted to a hospital and his condition is stated to be critical.

While the police said they have recovered a purported suicide note from the spot, they are investigating the murder by taking into account all possible angles.

“We have recovered a purported suicide note from the spot. It has four lines in Bengali. The rest is written in English. The letter purportedly written by Jadunath states that he killed his wife and tried to commit suicide. However, we are investigating the case from all angles,” Bidhannagar Police Commissioner Gaurav Sharma said.

“The autopsy of the woman’s body will be conducted. There will be a forensic examination. Jadunath Mitra lived with his wife on the second floor of the house, while the lower floors were given on rent. The wife’s body was recovered from the toilet on the second floor. Jadunath was rescued from near the dining table. Prima facie, it appears that the woman was murdered,” the police commissioner said, adding that the probe will also try to find if some outsider was involved in the murder.

Sources in the police said that a blood-stained knife was found near the spot where the woman’s body was found.

The murder came to light after the house help reached the Mitra residence in GD Block in Sector 3 of Salt Lake on Wednesday morning.