Police Maj. Keith Meadows said the performer, whose real name is Mario Hamilton, was fatally shot in the chest after getting into an argument with another individual.
"It appears the victim was scheduled to do a photo shoot," Meadows told The Associated Press. "Before the video shoot took place, it appears the victim and suspect got involved in a verbal altercation. We don't know what that altercation was about."
"The suspect produced a weapon, discharged that handgun one time, striking the victim in the chest," Meadows said.
The performer was transported to Grady Memorial Hospital where he was pronounced dead.
Meadows said police have not been able to identify the shooter. He said 13 to 20 people were in the small office-type building at the time of the shooting, which took place around 5:30 p.m., but they were in different places.
"We've questioned a number of witnesses inside the recording studio at this time." Meadows said.
Police have not recovered the handgun that was used.
"Right now we're just trying to....identify who may have seen what, really just trying to put the pieces of the puzzle together," he said. "It seems everybody witnessed something very different. We're just trying to go back and make sense of everything."
Meadows said the victim was in his early 20s and resided in the Atlanta area.
Many fans were posting messages late Friday night on the rapper's Facebook page.