The 911 tapes from a frightening standoff and shooting at an Atlanta-area school show how a school employee’s calm demeanor and kind approach helped end the ordeal without any injuries.

Police said Wednesday that school bookkeeper Antoinette Tuff was heroic in how she responded after being taken hostage a day earlier by Michael Brandon Hill, a 20-year-old man with a history of mental health issues. Hill went to the school armed with an AK 47-style rifle and nearly 500 rounds of ammunition, police said.

On a recording of a 911 call released Wednesday, Tuff can be heard relaying messages from Hill to DeKalb County emergency dispatchers before persuading him to surrender. She tells the dispatcher that Hill said he wasn’t there to hurt the children but wanted to talk to an unarmed officer.

“He said, ‘Call the probation office in DeKalb County and let them know what’s going on,’” Tuff is heard telling the dispatcher. “He said he should have just went to the mental hospital instead of doing this, because he’s not on his medication.”

No one was injured, but police said the suspect shot into the floor and exchanged gunfire with officers who had surrounded Ronald E. McNair Discovery Learning Academy in Decatur, a suburb east of Atlanta. The school has 870 students in pre-kindergarten through fifth grade.

The exchange between Tuff and the suspect was captured on a recording of a 911 call made by school officials to dispatchers.

Tuff begins by telling Hill of her own struggles, including raising a disabled child by herself. The bookkeeper reassures him by saying he didn’t hurt anyone, hadn’t harmed her and could still surrender peacefully.

“We’re not gonna hate you, baby. It’s a good thing that you’re giving up,” Tuff says after having Hill put his weapons and ammunition on the counter. Tuff tells Hill she loves him and will pray for him.

Before he surrendered, Tuff took to the school’s public address system to say Hill was sorry for what he’d done and didn’t want to hurt anyone — although the lockdown remained in effect.

Hill is charged with aggravated assault on a police officer, terroristic threats and possession of a firearm by a convicted felon. Police declined to discuss what he told them when questioned.

“We have to make a reasonable assumption he was there to do harm to someone,” DeKalb County Police Chief Cedric L. Alexander said.

The DeKalb County Public Defender’s office said in a statement that it was representing Hill, calling him “a young man with a long history of mental health issues.”

“Mr. Hill is being represented by members of our Mental Health Division, and he has decided to waive his first appearance today,” the statement said. “We are all very thankful that no one was hurt in this incident and that all of the children are safe.”

One of the office’s attorneys, Claudia Saari, wrote in an email that a preliminary hearing is scheduled for Sept. 5.

Police said Hill got the gun from an acquaintance, but it’s not clear if he stole it or had permission to take it. His motive is still unclear.

Law enforcement officers praised Tuff for helping to avert a potential tragedy.

“She was a real ally,” Alexander said. “She was a real hero in all of this. She just did a stellar job. She was cool, she was calm, very collected in all of this, maintained her wherewithal.”

Tuff told WSB-TV in Atlanta that she tried to keep Hill talking to prevent him from walking into the hallway or through the school building.

“He had a look on him that he was willing to kill — matter of fact he said it. He said that he didn’t have any reason to live and that he knew he was going to die today,” Tuff said.