Police told ABC13 that someone who was going to buy the apartment was cleaning it just before midnight Thursday at Club Creek near Woodfair when they smelled a strong odor. Neighbors in the complex have even noticed flies on the windows.
Investigators later discovered the body wrapped under a mattress. It's unclear if the body is of a woman or man or how long it has been there.
Investigators said the apartment is connected to the case of 24-year-old Carlos Rios, a man who was reported missing in March.
Family members told ABC13 that Rios would visit a friend at that apartment often. That friend was Jesus Cardenas, the man who was identified last month as a person of interest in Rios' disappearance.
Investigators had searched Cardenas' apartment when Rios was reported missing. He was arrested and later released on a narcotics charge. Now he is nowhere to be found.
Detectives were investigating Rios' disappearance as a possible homicide. However, at this point, they cannot confirm Rios was the one found overnight.
Investigators said there were signs of foul play in and outside.
Follow Miya Shay on Facebook and Twitter.
Follow Steve Campion on Facebook and Twitter.