An unidentified woman’s headless, decomposed body was found wrapped in a plastic bag inside the sewer of a building in Delhi’s Vasant Vihar locality on Friday night, PTI reported on Saturday. It was traced after the foul smell from the sewer tank became unbearable.

“The body was so decomposed that initially, it was difficult to establish whether it was a man or a woman,” a senior police officer told Hindustan Times. A tattoo of a leaf was found on the lower side of her neck. The first priority is to identify the woman, the police said. A case of murder against unknown persons has been registered.

The four-storey building in Munirka has 31 rooms rented out to students and professionals, according to authorities. They found that four rooms in the building had been kept locked the past few days.

Additional Deputy Commissioner of Police (South) Nupur Prasad told The Times of India that CCTV footage from the area was being scanned. The body appeared to be of a woman between 20 and 25 years of age, and from its state of decomposition, it seems she was murdered about a week ago, she added.

The owner of the building and his sons are being questioned. Residents of the building are suspected to have had a hand in the murder, according to the report.