Fulton County's 911 director, Alfred Moore, says it began Saturday afternoon when Darlene Dukes called 911 for help because she was "in respiratory distress."
Moore says the 911 operator misheard the address Dukes gave and sent crews to Wells Street in Atlanta when Dukes was actually at home on Wales Street in Johns Creek, north of Atlanta.
"My child would be alive today if they had responded timely," Darlene Dukes' mother, Ida, told CBS affiliate WGCL-TV.
Moore says the operator should have noticed that the call was coming from a cell tower in north Fulton County, not Atlanta.
The mistake caused a 25-minute delay in response.
Moore says the 911 operator has been fired.