WSB-TV reports (http://2wsb.tv/2oblG1c ) that the shooting happened in the College Park area, just southwest of Atlanta, shortly before 7 p.m. Thursday.
Fulton County police say the children were playing in a bounce house when the shots were fired.
Deanna Titus tells WSB that her grandson was shot in the back.
Conditions of the injured people were not immediately known.
The television station reports that investigators found at least 40 shell casings, and that unknown people in a vehicle were seen leaving the scene.
No arrests have been made.
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