The gunman surrendered after about an hour of negotiations and was taken into custody, Police Chief Thomas Bauer said. He did not release the man's name.
Bauer said officers were called to the Comfort Suites after a man indicated he had killed "some people." Officers entered the hotel and found the victims. Two were taken to hospitals.
"Dozens and dozens of shots were fired," Bauer said.
One of those shot appears to have been a man who came out of a room to see if he could assist, the chief said.
Tony Henderson, 33, of Atlanta, said he awoke about 3 a.m. to hear "police running around." He said police told him the shooter had a dispute with his girlfriend who was staying at the hotel.
Henderson said the shooting took place in a room and a hallway on the third floor.
Police would only say that the second and third floors were a crime scene, and did not say whether the gunman was staying at the hotel or explain his motive.