DECATUR, Georgia (USA TODAY) The man accused of opening fire in an Atlanta-area elementary school had 500 rounds of ammunition when he was arrested after a shootout with police, authorities said Wednesday.
In a 911 tape released Wednesday, the school bookkeeper talking to Michael Brandon Hill during the incident relayed to emergency dispatchers that the suspect said he was off his medications and thought he should have gone to a mental hospital.
Antoinette Tuff spoke to the 20-year-old Hill and told dispatchers that Hill said he had nothing to live for and wanted police to call the DeKalb County probation office.
WXIA-TV reported that the public defender for Hill waived his first appearance in DeKalb Magistrate Court on Wednesday.
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.
School bookkeeper Antoinette Tuff was being credited with calming the gunman down and convincing him to surrender. She told ABC News that Hill told her he had recently stopped taking medication. She said he added that he was going to die -- along with police officers.
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 will face 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.
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.
School employee Tuff said she worked to convince the gunman to put down his weapons and ammunition.
"He told me he was sorry for what he was doing. He was willing to die," Tuff said in an interview on ABC's World News with Diane Sawyer.
She said she told him her life story, including about the end of her marriage after 33 years.
"I told him, 'OK, we all have situations in our lives,'" she said. "It was going to be OK. If I could recover, he could, too."
Tuff said she asked the suspect to put his weapons and backpack down.
"I told the police he was giving himself up. I just talked him through it," she said.
King reports for WXIA TV in Atlanta. Welch reported from Los Angeles. Contributing: The Associated Press.
Michael King, William M. Welch and John Bacon, USA TODAY