Sheriff Ronnie Strength said 2½ hours of negotiations did not appear to be easing tensions, and the woman, identified as Georgette Reid, was getting increasingly dramatic.
Fearing for the childs life, the SWAT team set off two diversionary flash grenades and entered the Sunny Day Drive home in south Augusta .
The standoff began about 3 p.m. Thursday after a call to the police about a disturbance involving a knife, Sheriff Strength said. When a deputy arrived, Latoya Lewis ran up to him with severe cuts to her head and arm, saying her son was in danger of being harmed by Ms. Reid.
Police officers tried to enter the residence, but Ms. Reid refused to let them inside, barricading herself in a back room .
We were advised by her if anybody came in she would cut the childs throat, the sheriff said.
More than a dozen marked cars, the Richmond County SWAT team and a mobile command center were dispatched to the scene. Road deputies blocked the entrance to the neighborhood and closed a portion of Brown Road around the area.
The conversation was getting more dramatic with the hostage-taker, and we felt the childs life was in danger, Sheriff Strength said.
At 5:38 p.m., two loud bangs, accompanied by bright flashes, were heard behind the residence.
That provided a second or two diversion, Sheriff Strength said.
The first SWAT team member who entered the back room saw the butcher knife pressed against the childs throat, shot Ms. Reid in the shoulder, quickly grabbed the child and took him out of the room.
The conditions of the boy and Ms. Reid were not made public Thursday night.
The child was undergoing surgery at Medical College of Georgia Hospital and Clinics, the sheriff said.
Ms. Reids injuries did not appear life-threatening, he said.
The GBI was called in to investigate as it does routinely in police-related shootings . It was the third in Richmond County in just over a month. Two others resulted in deaths.