A March 2013 booking photo shows Michael Brandon Hill. Hill, 20, was arrested in Decatur, Ga., Aug. 20, 2013, after police say he fired shots at them with an AK-47 from inside a suburban Atlanta elementary school. No students or officers were injured. (Photo: Henry County Sheriff's Office via AP) 
 
 DECATUR, Ga. — A 911 tape released Wednesday reveals the courageous efforts of a bookkeeper who talked a gunman into putting down his weapon after he walked into her elementary school with an automatic rifle and almost 500 rounds of ammunition. 
 
 Michael Brandon Hill, 20, is accused of opening fire in the Atlanta-area school Tuesday. Antoinette Tuff spoke to Hill while on the phone with the 911 operator. She said Hill said he was off his medication and that "he don't care if he dies, he don't have nothing to live for," Tuff told the operator. "He said he's not mentally stable." 
 
 Later, she talked him into surrendering. 
 
 "He's laying on the floor. He's got everything out of his pockets. There isn't anything. The only thing he has is his belt. Everything is out of his pockets. Everything is sitting here on the counter, so all we need to do is they can just come in, and I'll buzz them in." 
 
 When the situation had ended, Tuff finally broke down. 
 
 "I'm going to tell you something baby — I've never been so scared in all the days in my life," she told the dispatcher. 
 
 Authorities were still trying to determine why Hill fired at least six shots with an assault rifle at Ronald E. McNair Discovery Learning Academy on Tuesday. Police returned fire; no one was injured. 
 
 Investigator T.L. Wortham of the DeKalb County Sheriff Department's Fugitive Unit told WSB-TV that as officers were apprehending the suspect, he said, "I'm sorry, I'm off my meds." Several weapons were seized, Wortham said. 
 
 Hill faces charges including aggravated assault on a police officer, terroristic threats and possession of a firearm by a convicted felon. 
 
 
 
 The suspect was arrested early this year for threatening to kill his brother. A police report from Henry County Police shows that he was taken into custody on Mar. 13 and charged with terroristic threats. 
 
 Hill's brother, Timothy Hill, told police in late December 2012 that the suspect sent him a Facebook message saying "that he would shoot him in the head and not think twice about it," according to the police report. 
 
 Timothy Hill, 22, told ABC News on Wednesday that the suspect has "long history of medical disorders" including bipolar disorder, and was bound to "do something stupid." Hill said he's not close to his brother and that Michael Hill was taking drugs for attention-deficit hyperactivity disorder as early as age 6. 
 
 "I had a feeling he was going to eventually, one day, do something stupid, but not of this magnitude," he told ABC News. 
 
 A police officer stands at the scene at Ronald E. McNair Discovery Learning Academy on Wednesday after a shooting incident was reported. (Photo: David Goldman, AP) 
 
 The elementary school of 870 students up to fifth grade is named for an astronaut who died aboard Challenger, the space shuttle that exploded after takeoff in 1986. Students returned to classes Wednesday, but they were held at a nearby high school. 
 
 DeKalb County Police Chief Cedric Alexander said the McNair school has a system requiring visitors to be cleared and buzzed in, and the gunman gained entry by slipping in behind someone authorized to enter. He said the man did not get past the school's main office. 
 
 King reports for WXIA TV in Atlanta. Welch reported from Los Angeles. Contributing: The Associated Press. 
 
 Read or Share this story: http://usat.ly/16bseaq ||||| Story highlights Suspect was arrested in March on suspicion of "terrorist threats and acts" 
 
 Police say Michael Brandon Hill, 20, faces aggravated assault charges 
 
 Witness to CNN affiliate WSB: Shooter said "he was not afraid to die" 
 
 Shooter was armed with an AK-47 "and a number of other weapons," police say 
 
 A man who opened fire at a Georgia elementary school Tuesday was armed with an AK-47 "and a number of other weapons," police said. 
 
 The shooter barricaded himself in the school's front office with employees before eventually surrendering to police, DeKalb County Police Chief Cedric Alexander told reporters. 
 
 No one was injured, authorities said. 
 
 Suspected shooter Michael Brandon Hill, 20, faces charges including aggravated assault on a police officer, terroristic threats and possession of a firearm by a convicted felon, police spokeswoman Mekka Parish said. 
 
 The shooter fired about six shots from inside the school toward officers as they approached outside, Alexander said, and police returned fire. 
 
 Michael Brandon Hill is charged with aggravated assault on a police officer, terroristic threats and possession of a firearm by a convicted felon, police said. 
 
 Police said it is unclear whether the suspect had any connection with the school, the Ronald E. McNair Discovery Learning Academy, which is about seven miles east of downtown Atlanta. Investigators think the gunman entered the school behind someone, Alexander said. 
 
 As the standoff unfolded, a caller told CNN affiliate WSB's assignment desk that she was in the school office with a gunman. 
 
 The man had a message he wanted the woman to share with the local television station, assignment editor Lacey LeCroy said, describing the conversation during WSB's newscast Tuesday evening. 
 
 "She said he told her to tell me he was not afraid to die," LeCroy said. 
 
 The gunman also threatened to harm police, the woman said, according to LeCroy. 
 
 Later, LeCroy heard gunshots crack over the television station's phone line. The woman in the school office wasn't sure who had fired, LeCroy said. 
 
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 Photos: Photos: Shots fired at Georgia school Photos: Photos: Shots fired at Georgia school Shots fired at Georgia school – A policeman walks in front of Ronald E. McNair Discovery Learning Academy after a shooting incident in Decatur, Georgia, on Tuesday, August 20. Michael Brandon Hill, 20, opened fire at the school armed with an AK-47 "and a number of other weapons," police said. There were no reports of injuries. Hide Caption 1 of 8 Photos: Photos: Shots fired at Georgia school Shots fired at Georgia school – A police officer interacts with students as they board school buses to take them to reunite with their parents. Hide Caption 2 of 8 Photos: Photos: Shots fired at Georgia school Shots fired at Georgia school – A child peers out the window of a school bus as the children are returned to their parents at a nearby shopping center Tuesday afternoon. Hide Caption 3 of 8 Photos: Photos: Shots fired at Georgia school Shots fired at Georgia school – Dekalb County Police SWAT officers run though the front yard of a home toward the elementary school on Tuesday. Hide Caption 4 of 8 Photos: Photos: Shots fired at Georgia school Shots fired at Georgia school – A police officer stands at the scene after the shooting. The school is located about seven miles east of downtown Atlanta. Hide Caption 5 of 8 Photos: Photos: Shots fired at Georgia school Shots fired at Georgia school – Nicole Webb gets emotional while waiting for her 9-year-old son. Hide Caption 6 of 8 Photos: Photos: Shots fired at Georgia school Shots fired at Georgia school – Parents cheer as buses arrive with students on board. Hide Caption 7 of 8 Photos: Photos: Shots fired at Georgia school Shots fired at Georgia school – Five-year-old Skyler Worthey, center, is reunited with his family. "Everybody's safe," said DeKalb County Schools Superintendent Michael Thurmond. Hide Caption 8 of 8 
 
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 Investigators initially suspected there could be explosives in a vehicle the shooter parked outside the school, but police found no explosives inside, Parish said. 
 
 Teachers and administrators guided students out to a lawn outside the school's gym, where they remained while investigators combed the school to ensure there was no other threat. Concerns about explosives forced SWAT teams to cut a hole in a fence by the school and evacuate students through the yard of a neighboring home, Alexander said. On a nearby street, school buses waited to take them to safety. 
 
 "This was a very unusual situation where we had to get the kids away from any possible explosives," Alexander said. 
 
 This was the second arrest in six months for Hill, of DeKalb County. In March, he was arrested in neighboring Henry County on suspicion of "terrorist threats and acts," according to a record in the county sheriff's office. He was released on bail five days later. Information on what led to that arrest or whether the case is resolved wasn't immediately available. 
 
 Students were reunited with their parents at a nearby shopping center Tuesday afternoon. The children smiled and waved, and parents cheered, as each school bus arrived with students aboard. 
 
 "Everybody's safe," DeKalb County Schools Superintendent Michael Thurmond said. 
 
 "This thing came out for the best," said Dale Holmes, DeKalb County's assistant police chief. "Thank God no one was hurt -- not even the suspect."
– Neighbors of Michael Brandon Hill, the man who allegedly walked into a Georgia elementary school wielding an AK-47 and demanded to speak to a TV station, have familiar things to say about the suspect. Hill is "just an average guy," a man who lives across the street from the home Hill shared with five other people tells the Atlanta Journal-Constitution. Other neighbors describe him as quiet and polite and say he could often be seen taking care of three children who apparently lived at the same address. But Hill, who surrendered to officers after firing several shots at them, was no stranger to police, ABC reports. In March, he was arrested for alleged terrorist threats and acts and was sentenced to three years' probation and anger management. He now faces charges including aggravated assault on a police officer, terrorist threats, and possession of a firearm by a convicted felon, and investigators say they're unsure of his motive. Hill lived about three miles from the school but no other ties to it have been uncovered.