The Georgia Department of Early Care and Learning launched the investigation Thursday, after surveillance video surfaced of the fight inside the McGarity School of Prep in McDonough.
Surveillance video aired by WSB-TV shows fists flying as adults battle each other, crashing into cribs and a mechanical swing.
The video shows a woman racing to rescue one toddler when the fight comes within inches of the child. Another toddler is seen wandering toward the combatants, eventually hiding behind a woman and clinging to her leg.
A state official said the video is a year old, but the agency that regulates daycares opened the probe this week after learning of its existence.
"We have no records indicating that this alleged incident at McGarity School of Prep, at 1285 McGarity Road in McDonough, Georgia, was ever reported to our agency by the provider, the parent or local authorities," Reg Griffin, a spokesman for Bright from the Start: Georgia Department of Early Care and Learning, said in a statement.
"As a result of receiving this video from December 13, 2012, we are opening an investigation into the incident," Griffin added.
McDonough police, who investigated the case, said the dispute involved a parent and employees of the daycare.
"We are very concerned about the kids at that day care for their safety," said Darryl Scott, the attorney for the parent, David Gray.
A telephone message from The Associated Press on Friday was not immediately returned by the daycare's owner. The owner told WSB that she was fearful for children in the day care and was defending herself during the confrontation.
Information from: WSB-TV, http://www.wsbtv.com/index.html
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