The discovery was made behind the Colonnades Condos on North Decatur Road by someone walking through a wooded area.
"We were watching when they pulled a body from behind the building," said one witness.
Channel 2 Action News reporter Darryn Moore spoke with detectives as they worked to identify the victim.
SLIDESHOW: Body Found In DeKalb Woods
Raymond Johnson said detectives searched the condo he rents as part of the investigation.
"They said the murder took place at least two weeks ago and that somebody buried the body in the back of the building," said Johnson.
Police said they haven't determined a cause of death, but they are calling the death suspicious until they have an official cause from the medical examiner's office.