Police suspect that the husband first killed his wife and then killed himself. (FILE PHOTO)

Partially decomposed bodies of a man and a woman were found from an apartment in Uttar Pradesh's Noida on Wednesday, at least four days after the incident, police said.

Shashi Tyagi, 56, and his 52-year-old wife Renu Tyagi were residents of Supreme Tower in Noida Sector 99. The matter came to light after their neighbours complained of a foul odour coming from the apartment, the police said.

"When police were alerted, they reached the house and had to break open the door, which was bolted from inside. The husband's body was found hanging from a ceiling fan in one room, while the wife's body was lying under the bed in the other room," a police official said.

"The bodies had started decomposing and appeared that the death took place four-five days ago," he said.

Police suspect that the husband, a property dealer, first killed his wife and then killed himself as they were "facing financial troubles".

"No suicide note has been found from the apartment and the bodies have been sent for post-mortem. The exact cause of deaths could only be ascertained after post-mortem and other details were being gathered," the official said.

Officials from Sector 39 police station said probe was underway and CCTV footages of the residential tower were also being checked as part of procedure.

The couple did not have any children and were living in the house on rent since 2016, the officials said.