(DECATUR, Ga.) -- The man who allegedly exchanged gunfire with officers inside an Atlanta-area elementary school has a "long history of medical disorders," according to his brother, who said suspect Michael Hill was bound to "do something stupid."
"I honestly can tell you he has got a long history of medical disorders, including bipolar, and that could make you snap on a dime," Timothy Hill told ABC News. "My moms almost looked like a drugstore at one point. There was so many different medications he was on."
Police said Michael Hill, 20, will face charges including aggravated assault on a police officer, terroristic threats and possession of a firearm by a convicted felon.
Timothy Hill, 22, said he's not close to his brother and thinks he last saw him in January 2011. Timothy did not disclose his brother's complete mental health history but said he was taking drugs for treating attention-deficit hyperactivity disorder as early as age 6.
Timothy said his brother had once threatened to kill him.
"I had a feeling he was going to eventually, one day, do something stupid, but not of this magnitude," Timothy said.
Michael, the lone suspect, allegedly entered Ronald E. McNair Discovery Learning Academy in Decatur, Ga., on Tuesday, carrying an AK-47 assault rifle and other weapons, Chief Cedric Alexander of the DeKalb Police said.
No one was injured and Michael did not make it past the main office inside the school, police said.
In the office, Michael came face-to-face with Antoinette Tuff, the school's bookkeeper, who said she was the one who eventually convinced him to empty his pockets and backpack of ammunition and to get down on the floor so police could apprehend him.
Michael, according to Tuff, said he had no reason to live because nobody loved him.
"And I just explained to him that I loved him," Tuff told ABC News in an exclusive interview Tuesday night. "I didn't know much about him. I didn't know his name but I did love him and it was scary because I knew at that moment he was ready to take my life along with his, and if I didn't say the right thing, then we all would be dead."
A man with the same name and age was arrested five months ago in McDonough, Ga., according to online records and court records. He entered a negotiated plea on July 16 and was sentenced to three years' probation and anger management.
During the standoff, Tuff said the suspected gunman "went outside several times and shot at police officers."
He also allegedly ordered staffers to call a local television channel, ABC affiliate WSB-TV, to request that a camera crew record him "killing police," WSB reported.
"He said that he didn't have any reason to live and that he was going to die today," Tuff said. "He was going to end his life and take all of the cops and everybody with him."
Tuff said she tried to keep the assailant calm by asking him his name but, she said, at first he wouldn't tell it to her. Then, he began listening to her tell her life story. She said she told him about how her marriage fell apart after 33 years and the "roller coaster" of opening her own business.
"I knew at that time it was bigger than me," she said. "He was really a hurting young man, so I just started praying for him. And just started talking to him and allowing him to know everything that was going on with me and that everything was going to be OK."
During the standoff, Michael called someone on the phone and Tuff said she heard the person crying. Tuff offered to talk to the person over the phone, but Michael said, "'No, it is already over with, I already started shooting, there's nothing you can do.'"
Then, Tuff made the request that she said helped end the standoff. She asked the suspect to put his weapons down, empty his pockets and backpack and lie on the floor.
"He brought a gun bag, a book bag, a bag full of ammunitions in there, a bunch of magazine clips in there, a whole lot of stuff," she said.
Police, including U.S. Marshals, entered the school and found the suspect in the office. He allegedly exchanged fire with the officers but ultimately surrendered, Alexander told reporters.
"Once we found out where he was located inside the school we actually gained entry through a side building in the school and luckily we had an officer who was familiar with the layout of the school and made it directly to the office where Antoinette had the man already on the ground so we could apprehend him and take him into custody," Dekalb County Police Det. Clay Hobbs said Wednesday on ABC's Good Morning America.
SWAT teams were sent classroom to classroom to evacuate students, some as young as pre-kindergarten. Authorities have yet to establish a motive or determine whether the suspect had a link to the school.
Authorities believe the man might have entered the school by closely following a person authorized to enter the building. But once inside, he only went as far as the front office.
The shooting came on the second week of classes at the charter school. Classes for the elementary students will be held at McNair High School on Wednesday. Tuff said she will be returning to work later Wednesday morning.
"Yes, I will be back," she said, "sitting in that same seat, blessing that next person."
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