According to Atlanta police, they were called to a parking deck at the Berkeley Heights apartment complex on Northside Drive just before 1 a.m. When they arrived, officers found three people near the fourth deck who had been shot. [DOWNLOAD: Free WSB-TV News app for alerts as news breaks] Channel 2’s Darren Moore spoke with investigators at the scene, who told him one man died and two others were taken to Grady Memorial Hospital with gunshot wounds to the leg. Investigators say they believe an argument started in the parking lot between father and son and the man who died, which ended with both sides shooting each other. It is unclear what started the argument or who fired first. Father and son are said to be in their 40s and between 18 and 22 years old. The dead victim is said to be 20 years old. None of their identities have been released. Witnesses told police they saw a silver sedan leave the parking lot shortly after the shooting. Police are continuing to search for the vehicle and its driver. FILM STORIES: Detectives say they were able to recover several guns and shell casings in the parking lot. Investigators are still working to learn what sparked the violence. [SIGN UP: WSB-TV Daily Headlines Newsletter] IN OTHER NEWS: Non-emergency calls increase delay in response times, Atlanta 911 dispatch center says ©2022 Cox Media Group