The woman, whose severed head was found in a south Kolkata garbage vat on Friday, was identified as Khadija Bibi, a domestic help from Diamond Harbour, South 24 Parganas, 60 km from the state capital.
Police have detained a brother-in-law of the victim, who paints houses.
He, reportedly, used to work in the same area in connection with the murder.
The investigators, however, are yet to recover the body or body parts of the victim.
"We are questioning the suspect. He has been picked up on the basis of information provided by our sources and footage of CCTV cameras in which he was seen carrying the plastic bag in which the severed head was found,” said Bidisha Kalita, deputy commissioner of police, south suburban division.
Also read: Severed head found in Kolkata’s Golf Green, probe underway
Preliminary investigation reveals that Khadija was in her late 30s. And was in an illicit relationship with the suspect.
She got separated from her husband three years ago and started working as a domestic help in Jadavpur and Golf Green area in South Kolkata.
“We came to know Khadija was into a relationship with her brother-in-law for the past two years. We are investigating whether a strained relationship between the two led to the incident,” said a police officer.
Khadija’s severed head was found in the road-side vat at Golf Green, a posh residential area in South Kolkata. The vat is located behind a residential high-rise building.
As per a preliminary examination, “Khadija was first hit with a blunt weapon on her head and then her head was severed,” said a police officer.