Police helicopters and a K9 unit were searching the area Saturday night.
When officers arrived at the scene earlier in the day, they found one victim suffering from a gunshot wound in the cul-de-sac. He later died at a local hospital.
Officers then searched a nearby home where a garage door was open, and found two more deceased men.
Police did not have a suspect description and were investigating possible motives.
Contact GCPD detectives at (770) 513-5300 with information or tips on the shooting.